The Certain Conscience

210. Principles. 1. We are bound to follow a certain conscience where it prescribes or prohibits.

For certain conscience is the law itself certainly known by us and applied to a particular action, if conscience is supposed true; but we are bound to follow law certainly known; therefore we are bound to follow certain conscience, at least if it is also true.

2. We are bound to follow a certain conscience where it prescribes or prohibits, even if it is invincibly erroneous, and we can follow the same without sin where it permits something.

The reason for the first is that the will, since it is a blind faculty, in order to act rightly is bound to follow the guidance of the intellect certainly prescribing or prohibiting; therefore it is bound to follow true conscience equally as conscience invincibly erring, provided it is certain. The reason for the second is that one following a permitting conscience wills an action which he judges licit, which cannot be sin.

It is asked whence erroneous conscience receives the force of obliging; for since it obliges insofar as it announces the divine law, erroneous conscience, inasmuch as it does not in reality announce divine law, seems unable to oblige. It must be said that erroneous conscience draws the force of obliging from the universal principle of law: good is to be done, evil is to be avoided, as far as can be done, i.e. as it is manifested to us through conscience; whence we are bound always and in every case to obey certain conscience. Therefore erroneous conscience does not oblige by force of the particular precept which it announces, but by force of the universal precept by which we are bound to do good and avoid evil insofar as we can.

a. The affirmation supposes that he who acts with invincibly erroneous conscience preserves freedom. For in those things which cannot be avoided, sin cannot be committed from erroneous conscience, because the action or omission is altogether involuntary. He who thinks that dishonest or blasphemous thoughts already are sins does not sin, even if he has thoughts of this kind, because he cannot bring it about that they do not enter the mind. Likewise an imprisoned person who erroneously thinks that he sins because he omits Mass does not in reality sin.

b. "Hence if conscience dictates to someone that he is bound to lie in order to aid a neighbor in danger, he sins against charity if he does not lie." - "He who thinks there is a fast when there is not, because of erroneous conscience sins if he does not fast."¹

c. He who places a work evil in itself, which from erroneous conscience he thinks to be good, not only does not sin, but according to the opinion of many exercises a good work and, with the suppositions to be supposed, also merits through it.

d. Sin committed from erroneous conscience is of the same gravity and species as if it had been committed from true conscience. He who, erroneously thinking that Mass must be heard, omits it, sins gravely against the precept of the Church, and in confession it suffices to say: I omitted Mass. He who strikes a man, erroneously thinking that he is a priest, commits sacrilege just as if in reality he had struck a priest. Yet if the confessor notices that the penitent has sinned from erroneous conscience, let him ask him whether he really judged that he was sinning gravely, and let him instruct him concerning the truth of the matter.²

e. If, therefore, conscience dictates that it is licit to steal in order to aid a poor man, theft from invincibly erroneous conscience would not be a sin.

3. A vincibly erroneous conscience, whether it prescribes or permits, may neither be followed nor acted against; rather, we are bound to lay aside the error before the action: for one acting thus would expose himself to the danger of sinning. Yet if there were question of a good act which someone thinks to be prescribed, he could follow a vincibly erroneous conscience and would not be bound to lay aside the error.

"He who thinks, but with doubt, that he must steal from a rich man in order to aid one in need, sins whether he steals with a conscience of this kind or does not steal. Therefore before the action, if it can be done, he must lay aside the error by inquiring into the truth."³ - But he who with doubt thinks that today he must hear Mass and goes to hear Mass is not bound, by inquiring into the truth, to lay aside the error.

Note. In order that a confessor may discern whether conscience was invincibly or vincibly erroneous, let him ask the penitent: a. whether he noticed some indecency in the act or at least doubted concerning its liceity; b. whether conscience dictated to him that someone should be asked about that matter. But if he denies each, the error was invincible; if he affirms either one, the error was vincible and culpable, and indeed gravely culpable if he apprehended the matter under discussion as a matter of great moment.

¹ Gury, Compendium theologiae mor. I. n. 38.

² Cf. Lugo, De poenit. disp. 16. n. 499 ss.

³ Gury, l. c. n. 38.

211. On lax conscience. Lax conscience sometimes denotes a habit, namely that disposition of soul which tends to extending moral liberty more than is right; if it signifies an act, it is a judgment which from a slighter motive judges that to be licit which is illicit, or that to be a light sin which is grave. And consequent lax conscience is a judgment which from a slight motive judges that there was not grave sin where in reality grave sin was committed.

Principles. a. Ordinarily those who, knowing that they have a lax conscience, transgress a precept in a grave matter, sin gravely: for either they have a confused knowledge of grave sin, or if they do not have this, those who in a grave matter knowingly follow a lax conscience knowingly expose themselves to the danger of violating a grave precept. Nor does the error by which they judge that there is no sin excuse them, because the error is voluntary in its cause.

Those who do not know that they are of lax conscience and do not notice the malice of the action even confusedly are excused from sin because of ignorance. Indeed even he who knows that he is of lax conscience can be immune from mortal sin, namely where he notices neither the malice of the action nor the obligation of investigating its malice more accurately, not even confusedly.

b. In doubt concerning full consent to sin, it must be presumed that they fully consented, just as those who are of timorous conscience, in doubt, are presumed not to have consented: for from things ordinarily occurring a conclusion is rightly made with moral certitude to a particular fact.

c. He who labors under lax conscience is bound under grave obligation to lay it aside, because he is bound to lay aside the habitual danger in which he is situated of sinning gravely.

212. On perplexed conscience. The rules to be observed by him who has a perplexed conscience, from St. Alphonsus (n. 10), are these:

a. If without grave damage he can defer the action, he is bound to defer it until he has consulted wise men, e.g. a confessor: for anyone is bound to avoid what he thinks is sin.

b. If he cannot defer the action, he is bound to choose that which seems to him the lesser evil: for he ought rather to avoid a greater evil than a lesser, e.g. transgression of the natural law than of positive law, if he cannot avoid each.

c. If he cannot discern the lesser evil, whatever he chooses, he does not sin; and this indeed even if through error he thinks that he sins, because the act which he places is not voluntary.

Let the example be a man who on a feast day, assisting a sick person, thinks that he sins if he remains, and likewise that he sins if he goes to church; or a priest who, making the sacrifice, thinks that he will sin if he repeats the form of consecration, and likewise that he will sin if he does not repeat it; or a confessor who fears that he will sin by denying absolution, because he wholly frightens the penitent away from the sacraments, and that he will sin by granting absolution, because he administers the sacrament to an unworthy person. Let him do what he wills: for no necessity of sinning exists.

218. Notion and division. Certain conscience is that by which the mind firmly judges, without fear of erring, that an action is good and licit or evil and illicit.

a. By reason of the motive, strict or perfect certitude is distinguished, which wholly excludes every doubt and every fear of erring, even an imprudent fear; and broad or imperfect certitude, which excludes only every prudent doubt, yet rests upon motives of such a kind as truly merit assent excluding prudent fear of erring.

Broad or imperfect certitude is customarily called moral certitude. This must suffice for us in many matters even of the highest moment, because in these matters we cannot have a greater and more perfect certitude, e.g. concerning the validity of baptism or priestly ordination. Nevertheless it must not be confused with moral certitude which is improperly called by this name and signifies nothing other than a certain greater degree of probability, which nevertheless does not exceed the limits of probability.

b. By reason of the object, speculative certitude is distinguished, which is concerned with abstract truths or with the liceity of an action in general, e.g. to plow is a servile work, or servile works are prohibited on a feast day; and practical certitude, which is concerned with the liceity of an action to be placed here and now, e.g. today, even if it is a feast day, it is lawful for me to paint.

c. By reason of the mode in which it is acquired, direct and indirect or reflex certitude is distinguished. Direct certitude is called that which arises from the internal principles of reason, which demonstrate the truth of the matter itself and the honesty of the action; indirect certitude is called that which arises from external (reflex) principles, which do not demonstrate the truth of the matter itself and the honesty of the action, but from which nevertheless the honesty of the action is certainly gathered.

Let the example be a judge who must condemn the guilty and absolve the innocent. Now if from the judicial acts the accused is demonstrated guilty, the judge has direct certitude of the crime committed and forms a directly certain dictate of conscience: this accused person must be condemned by me. But if from the judicial acts grave reasons show the accused guilty, but other grave reasons show him innocent, he does not acquire direct certitude concerning the committed crime and a directly certain dictate concerning the accused to be condemned or absolved; but by applying this reflex principle: in doubt favor is to be shown to the accused, he forms an indirectly certain dictate: this accused person must be absolved by me.

219. Principles. 1. Certain conscience alone is the right norm of our actions: for from the Apostle, everything which is not from faith, i.e. which is not from certain persuasion that the thing which is done is honest and licit, is sin.¹ Certainly, he who operates with a conscience which is not certain voluntarily exposes himself to the danger of transgressing the divine will; but one acting thus virtually consents to the transgression of the precept, and therefore sins formally. Wherefore it is never lawful to act without certain conscience concerning the honesty of the action.

2. In order that we may follow conscience, it suffices that it be morally certain with imperfect certitude: for in our moral actions that certitude must suffice, of which the very nature of things does not admit a greater; but moral matters for the most part admit no certitude other than moral or broad certitude. Besides, for operating licitly a truly certain persuasion concerning the honesty of the action suffices; but morally certain conscience is truly certain.

A negative doubt does not impede the certitude of conscience, because it is founded either upon no reason or only upon a lighter and empty reason and is known as such by the agent. Therefore he who acts with a doubt of this kind nevertheless has a practically certain conscience. From this it is clear that negative doubt is to be spurned and only positive doubt in a moral matter is to be attended to.

3. For operating licitly any practically certain conscience suffices, even indirect conscience; for in order to operate licitly nothing else is required except certain persuasion that the action to be placed here and now is honest; but any practically certain conscience supplies this persuasion, whether by direct or reflex certitude.

¹ Rom. 14, 23.

CERTAINTY in general is a firm assent of the mind to something known, without the fear of mistake. In mathematics and in other branches of exact science we can often attain absolute certainty, which rests on the evident truth of the principles which are employed to arrive at it. For anyone who is capable of following the demonstration there can be no manner of doubt that the angles of a triangle are together equal to two right angles. In the science of morality we have frequently to be content with a lower degree of certainty than this; there is often some obscurity about the principles to be applied, and human acts are not the matter of necessary and unvarying law. We have to be content with what is called moral certainty; but this again is of various degrees. I am morally certain of the existence of Berlin, though I never saw the city. Any person who doubted of its existence would be thought to be insane. The grounds on which the judgement that Berlin exists are based are so many and so strong that they leave no room for prudent doubt in the matter. In such cases we have perfect moral certainty. In other cases I may be conscious that mistake is possible but not probable, as when a man has been condemned on evidence which has satisfied a jury of intelligent men. In such cases if there can be no prudent doubt about the justice of the verdict I have moral certainty of an imperfect but real kind. If I could not safely rely in guiding my conduct on such a degree of certainty, I should have to abstain from action altogether. Ordinarily greater certainty cannot be obtained in human affairs.

In order to act lawfully and rightly, I must have at least moral certainty of the imperfect kind that the proposed action is honest and right. This degree of certainty will be sufficient, for ordinarily no greater can be had, as we have just seen. It is also required for right action; for if I am not at least to this extent morally certain that my action is right, I am conscious that it may be wrong. In this case I am bound to pause, and satisfy myself that it is right before acting; for if I do not do so my will is ready to embrace what may be wrong I am ready to do the action whether it is in right order or not. But such a will is malicious; it is not firmly set on doing what is right; and sin is thereby committed.

A subjectively certain conscience then, which tells me without prudent doubt that the action is right, is required for lawful action; “‘ All that is not of faith is sin,” as St Paul says.¹ It will be sufficient if we have imperfect moral certainty, as we have seen.²

¹ Rom. xiv 23.

² St Thomas, 2-2, q. 70, a. 2.

If I have this imperfect moral certainty that my action is right, I am justified in acting, and if with such certainty my conscience tells me that I am bound to act, I must do so, even though my conscience be erroneous. For my action is morally good if my will be good. My will is good when it tends to a good object as represented by my intellect, not as it is in itself. But if my will follows my conscience and determines on what it prescribes, my will then tends to a good object as represented by my intellect and is a good will. So that even though my conscience be erroneous, I am justified in following it, and I am bound to follow it when it prescribes any action to be performed.¹ This is true whenever I have a certain conscience—that is, when I have no doubt or suspicion about the honesty of my action, even though my conscience be erroneous. If I were the wilful cause of my conscience being in error by not taking means to inform it correctly, then any objectively wrong action that I perform is voluntary in the cause, and so far imputable to me, but here and now I must follow my conscience.

I am said to be bound by my conscience because it compels me to follow it under pain of doing wrong, committing sin, and being exposed to the pangs of remorse. It binds me also in the name of God, whose will it makes known to me, It speaks, therefore, with the authority of God, it sternly bids me follow his behests, and it reproves me with the authority of a superior if I neglect to follow its promptings. As representing the will of God its authority is greater, as St Thomas teaches,² than that of any merely earthly superior. .4. The question as to whether in any particular case a person acted with an erroneous conscience is a question of fact, which only he and God can decide. Still, following approved theologians, we may make use of certain presumptions drawn from the nature of things and from experience. It may be admitted that ignorant and dull people may have an invincibly erroneous conscience concerning the malice of merely internal sins committed in thought only; but we should except efficacious desires to do what is known to be wrong. A person can scarcely know that the external action is morally wrong and be ignorant of the malice of an effective desire to commit such an action.

Again, the first principles of morality, which are certain general axioms of conduct, such as, Do to others as you would be done by, can scarcely fail to be known by anyone who has the use of reason. Even the secondary principles of the moral law, or the precepts of the Decalogue, are usually known by those who have attained the use of reason among civilized men; if in any case there is ignorance of them, it is vincible ignorance, and so more or less culpable. Theologians readily admit the possibility of an invincibly erroneous conscience concerning the application of the general principles of morality to concrete cases. The theological disputes which they chronicle are proof of the fact. 1 St Thomas, 1-2, q. 94, aa. 4, 6.

¹ St Thomas, 1-2, q. 19, a. 5.

² De Verit., q. 17, a. 5.

Proposition. For acting licitly, certainty strictly so called concerning the honesty of the action to be placed here and now is required. This is clear, first, from Sacred Scripture. "But he who discerns, if he eats, is condemned, because it is not from faith. But everything that is not from faith is sin" (Rom. 14:23). Here St. Paul treats the controversy about the eating of foods which the Mosaic law prohibited. Moreover, the Apostle teaches that he sins who eats the aforesaid foods while discerning, Greek diakrinomenos, which in the context means: struggling with himself, doubting, hesitating,¹ whether the eating is licit. But according to the Apostle the reason is that every action placed without a firm persuasion concerning the honesty of the action is sinful. "It is said," says St. Alphonsus, "from faith, namely, from a certain dictate of conscience, so that a man is persuaded in his conscience that by acting he acts rightly" (I, 55). This interpretation is deduced from the context of the discourse (vv. 2, 14, 22), and even today is commonly admitted.² There is added, second, an argument taken from reason. Beyond doubt, he sins who wills and chooses an action, whether it is good or evil, whether it offends God or does not offend God. But one acts thus who wills and chooses an action about which he doubts whether here and now it is licit. Hence St. Augustine: "To do that which is uncertain whether it is a sin is a certain sin."³ St. Alphonsus asserts the same repeatedly (I, 22, 24; likewise I, 81 and Homo Apostolicus I, 65, where he teaches that not even a most probable opinion of itself and ultimately suffices).

Corollary I. Authors commonly teach that broad certainty suffices for acting licitly. But this is said less accurately; for broad certainty still admits prudent fear, or broad doubt. But it is not licit to place an action as long as one still prudently fears that it is formal sin, or a true offense against God. Moreover, this fear or broad doubt is easily excluded through some general reflex principle, for example: It is licit to follow an opinion certain in the broad sense; which principle others also call concomitant.

Corollary II. It suffices that someone in good faith be certain of the liceity of an action, even if the foundation on which the certainty rests is less solid. Nor is it required that someone reflexively judge that he is certain.

Corollary III. One who acts with a practical doubt concerning the honesty of an action commits as much and such a sin as that about which he doubts; for he perpetrates as much and such a sin as the danger to which he exposes himself (St. Alphonsus, I, 22). If only the notion of sin is apprehended, there is had a sin of unnamed species; concerning this, however, observe these words of St. Thomas: "When reason apprehends something as evil, it always apprehends it under some notion of evil; for instance because it is contrary to a divine precept, or because it is scandal, or on account of something of this kind; and then such an evil will is reduced to such a species of malice" (I-II, q. 19, a. 5, ad 3). "Yet it must be noted for practice, what many are ignorant of, that it is gravely illicit to act with a practical doubt about grave sin."⁴

¹ The source's Greek form is badly OCR'd; the intended term is diakrinomenos.

² That by "faith" supernatural faith is not understood, but a dictate of conscience, is clear from Lateran IV (c. 41); and that a certain dictate is understood is taught by Estius, Beelen, Cornely, Reithmayer, Bisping, and other interpreters commonly.

³ Bk. I, De Baptismo, c. 5.

⁴ Cf. Marc, n. 37; Vindiciae Alphonsianae, I, p. 504; Aertnys-Damen, I, n. 64.

Necessity of Certitude.—We must be sure we are right before we act; otherwise, we expose ourselves to the danger of sinning, and therefore commit sin (see 582). Hence, it is necessary to act with a certain conscience, and unlawful to act with an uncertain conscience. “If the trumpet give an uncertain sound, who shall prepare himself to the battle?” (I Cor., xiv. 8) may be accommodated to conscience. In Rom., xiv. 22, 23, the Apostle declares that he who acts with conviction is blessed, whereas he who acts in uncertainty is condemned. Examples: Sempronia doubts whether it is sinful to sew on Sunday; she is not sure, but has grave suspicions that sewing is servile work; if she goes ahead, she will be guilty of violating the law, as being willing to take the risk, and therefore the responsibility. Titus offers another a drink, being uncertain whether it has poison in it or not; he is guilty of sin, since he has no right to expose himself to sin and his neighbor to the danger of death.

Those persons who act with a doubtful conscience, and later discover that what they feared might be wrong was not wrong, or not so bad as they suspected, must bear in mind: (a) that their past conduct is not to be judged by their newly acquired knowledge, for that conduct must be judged by the knowledge had at the time. Example: Sempronia does some work on Sunday, doubting whether she is committing a grave or a slight sin. Later she discovers that it was really only a venial sin, and she congratulates herself that she did not sin seriously. Her judgment is wrong, because she did not know at the time of the work that it was not a grave sin; (b) that they must guide themselves in future acts by their newly acquired knowledge.

12. Certain conscience properly is that conscience which rests upon a certain motive; and consequently judges concerning the honesty or turpitude of an action to be done without fear of erring. Less properly, it is that which simply judges concerning the honesty or turpitude of an action without any fear of erring. The latter is certain only subjectively; the former is also certain objectively. Likewise, certain conscience can be certain strictly and broadly, or morally. Strictly certain conscience excludes every doubt, both prudent and imprudent. Broadly or morally certain conscience excludes only every prudent doubt. Its directive force as regards the licitness or illicitness of human acts, commanded or prohibited, is declared in the following propositions.

13. Only certain conscience is proximately directive of human acts. - Proof. "The command of one who governs has itself for binding in voluntary matters in that mode of binding which can befall the will, as bodily action has itself for binding bodily things by the necessity of coercion. But the bodily action of an agent never induces necessity in another thing except through the contact of its coercion with the thing upon which it acts. Hence neither is anyone bound by the command of some king or lord unless the command touches the one to whom it is commanded; but it touches him through knowledge. Hence no one is bound by any precept except through the mediation of knowledge of that precept. And therefore he who is not capable of knowledge is not bound by a precept. Nor is someone ignorant of a precept of God bound to doing the precept, except insofar as he is bound to know the precept. But if he is not bound to know, and does not know, he is in no way bound by the precept. As in bodily things, a bodily agent does not act except through contact, so also in spiritual things a precept does not bind except through knowledge." St. Thomas, De Veritate, q. 17, a. 3.

14. Therefore man is bound through knowledge, or certain knowledge, of the precept by which, however, he is properly bound. Hence the Holy Doctor goes on to say: "And therefore, just as the force by which touch acts and by which the power of the agent acts is the same, since touch does not act except by the power of the agent, and the power of the agent acts only through the mediation of touch; so it is the same power by which the precept binds and by which conscience binds, since the precept does not bind except through the power of knowledge, nor does knowledge bind except through the power of the precept. Hence, since conscience is nothing other than the application of knowledge to an act, it is clear that conscience is said to bind by the force of the divine precept. Therefore it must be said that man does not make a law for himself, but through the act of his cognition, by which he knows the law made by another, he is bound to fulfilling the law." But this act of cognition, according to St. Thomas, is nothing other than knowledge of the law, or certain cognition of the law. Any other uncertain cognition manifests not the law, but a doubt about the law, by which certainly the will cannot be bound.

15. According to the same Angelic Doctor, someone is bound by a precept in two ways: either because he has knowledge of it, or because he is bound to know it. But when, with moral diligence applied, the precept is not established, then neither is knowledge of the precept lacking, nor is he bound further to know it, since by hypothesis the diligence necessary for knowing it has already been applied, and it could not be known. Wherefore then knowledge of the law is lacking, and no obligation of the will can be had.

16. It is unlawful to act without conscience subjectively certain concerning the honesty of an action. - Proof. He who acts without this conscience wills an action concerning whose honesty or turpitude he is uncertain. But to will an action concerning whose honesty or turpitude one is uncertain is nothing other than to will it whether it be good or evil. But again, to will an action whether it be good or evil is illicit, for this is a will consenting to evil. Therefore. Moreover, the saying of the Apostle to the Romans is well known, 14:23: All that is not of faith is sin. That is, what is not from a certain persuasion that it is licit is sin. - St. Thomas, I-II, q. 19, aa. 3, 5; Quodl. 3, a. 27, ad 2; Quodl. 8, a. 13; L. I, n. 3; Suarez, tr. 3, d. 12, s. 3.

17. Sin does not have a special malice precisely from this, that it is against conscience, unless it is done in order that conscience may be overcome. The first reason is that this is intrinsic and common to every sin, that it be against conscience. The second reason is that there is then a directly willed contempt of the rule of every good operation, and thus one exposes himself to the danger of all crimes, which, as is clear, is a special and indeed most grave disordering of the will, against the natural inclination of the will toward good. - Lessius on q. 19, a. 6, d. 3; St. Thomas, II-II, q. 14, aa. 1, 4.

18. Likewise it is a special sin if someone sins from certain malice through contempt, casting away and removing that which could have impeded the choice of sin; and it is a sin against the Holy Spirit. Six species of this are enumerated: despair, presumption, impenitence or the purpose of not repenting, obstinacy or the purpose of adhering to sin, impugnment of acknowledged truth so that one may sin more licentiously, envy of fraternal grace, by which someone envies not only the person of his brother, but also the grace of God increasing in the world.

19. Only conscience subjectively certain is the rule of morals. But morally certain conscience suffices. - Proof of the first part. For, as is clear from the preceding proposition, nn. 13, 16, without this conscience one cannot act. Besides this conscience, no other subjectively more perfect conscience is given. Therefore one can act with this alone; and accordingly this conscience alone is the rule of morals. Proof of the second part. 1. From the common sentence of the doctors and universal practice. 2. Because very often another certainty cannot be had, and no one necessarily sins. 3. Because, with this moral certainty standing, one acts prudently; for moral certainty, although it does not exclude every doubt, both prudent and imprudent, nevertheless excludes every prudent doubt. Therefore. - Rom. 14:23; c. Litteras 13, De Restitutione Spoliatorum; St. Thomas, II-II, q. 47, a. 9 ad 2; q. 70, a. 2.

20. It is lawful to act according to certain conscience, even if it is invincibly erroneous. - Proof. He who acts thus wills, as far as lies in him, a good action, and consents only to a good action. But it is right to will this action. Therefore. Proof of the major: for nothing is willed unless it is first known. Therefore, with invincibly erroneous conscience standing, he who acts according to it wills, as far as lies in him, a good action, and consents only to a good action. - L. I, n. 5; Elbel 126.

21. Wherefore he who is persuaded in such a way that he ought to tell a lie in order to free his neighbor from a grave evil does not sin by lying; indeed, he places an act formally good. - Although erroneous conscience materially disagrees with the law, nevertheless one is bound by it, because erroneous conscience proposes error as law. Since obligation arises from law, in the aforesaid case of erroneous conscience, obligation does not arise directly from the law that one must lie, which does not exist; but it arises from the more general natural law of doing good and avoiding evil; and the evil to be avoided in the case is apprehended as a good to be done. St. Thomas, De Veritate, q. 17, a. 4 ad 3.

22. It is unlawful to act against certain conscience, even if it is invincibly erroneous. - Proof. He who would act thus would will an action which he judged prohibited; he would refuse one which he judged commanded. But it is unlawful to have this will, because it is a will consenting to evil. Therefore. "It must be said that, simply, every will disagreeing with reason, whether right or erring, is always evil." St. Thomas, I-II, q. 19, a. 5; 2 Sent., d. 39, q. 3, a. 3; Quodl. 3, a. 27; L. loc. cit.; Cajetan on I-II, q. 19, a. 5; Suarez, tr. 3, d. 12, s. 4.

23. Wherefore he who believes himself bound to tell a lie in order to free his neighbor from grave evil sins by not lying.

24. It is lawful to act according to certain conscience, although it is vincibly erroneous. - Proof. Because when an action is judged honest or base with certainty, the will acting according to this conscience pursues the honest and flees the base, which is wholly lawful. But that this conscience is vincibly erroneous does not make it that, when someone actually acts according to it, he sins; rather this makes it that the fault is only in the cause. Hence also the judgment concerning its gravity or lightness must be made not from the grave or light effect, but from the grave or light negligence in inquiring into the truth. Now when someone actually acts, if in no way does he attend to the erroneous conscience which he has, and has no suspicion concerning it, since by hypothesis there is here and now a certain conscience, he already acts not from a vincibly erroneous conscience, but from an invincible conscience. - La-Croix, l. 1, nn. 42, 43, 757, 760; Kenrick, 2nd ed., Mechlin, 1860, n. 36.

25. Wherefore he who here and now judges himself bound to commit theft in order to help a poor person does not sin by stealing. But those who are habitually of lax conscience ordinarily sin gravely by transgressing a grave precept, because ordinarily speaking they have at least some confused knowledge of it.

26. It is unlawful to act against certain conscience, even if it is vincibly erroneous. - Proof. Because then one would act against a certain judgment; and he would will the action which he judges prohibited, and would refuse the action which he judges commanded; which will is evil, for it is affected toward evil. Therefore. St. Thomas, I-II, q. 19, aa. 5, 6; Suarez, tr. 3, d. 12, s. 4; Elbel 122, 137, 138; L. I, n. 4; La-Croix, l. 1, nn. 42, 43, 757. - "And therefore it must be said that every conscience, whether right or erroneous, whether concerning things evil in themselves or concerning indifferent things, is obligatory, so that he who acts against conscience sins." St. Thomas, Quodl. 3, a. 27; Quodl. 8, a. 15.

27. "A sin committed against conscience has its species from the particular matter in which it is thought to be concerned, or from order to the particular precept to which it is thought to be opposed. For example, if you think a thing which you take is not yours, although in reality it is yours, it will be the sin of theft; if you think it is against the obligation of a vow, it will be the sin of sacrilege. The reason is that sins receive their species from the object either of the external action or of the will. Nor does it matter whether this object is really evil, but whether it is apprehended as evil; because the will is borne toward it as it is proposed by reason." Lessius on q. 19, a. 6, d. 3; St. Thomas, I-II, q. 19, a. 5 ad 3.

28. It is no sin to act against certain erroneous conscience if liberty of acting is lacking. - The reason is clear, because where there is no freedom, there is no sin. And thus he does not sin who believes that he sins, while having base thoughts or suffering base movements, which, although he detests them, he nevertheless cannot impede.

29. Can someone labor under an invincibly erroneous conscience concerning depraved desires and other merely internal acts, if no external action follows? - Speaking explicitly and generally about desire, Elbel has this, n. 127: "That many, at least among the more unlearned and less educated, can inculpably persuade themselves that desires of this kind are not evil unless they are completed by deed, seems sufficiently certain, and Sanchez, Stoz, and La-Croix expressly teach it." St. Alphonsus says concerning this opinion, I, n. 9: "I could never consider it probable.... With other learned recent authors I consider it little probable." The reason for this sentence is that if someone certainly knows the malice of the external action, and nevertheless wills to execute it, he already knows that he wills evil. How, therefore, will he be excused from sin? But as regards simple delectation, invincible ignorance can more easily be present; for the tendency of the will into evil is not so evident as in a desire that is of itself efficacious. And the same also seems to be said of an inefficacious desire.

30. Can there be an invincibly erroneous conscience concerning precepts of natural law? - "It is certain that in the first principles of natural law principles, as also in proximate conclusions and in the certain obligations of one's proper state, invincible ignorance is not given, because by the very light of nature such things are known to all, except to those who close their eyes lest they see them. But on the contrary the unanimous sentence of theologians is... that in conclusions which are mediate and obscure, or remote from the principles, invincible ignorance certainly is given and must be admitted," L. I, n. 8, 170 seqq.; Struggl, tr. 3, q. 1, n. 10-13; St. Thomas, Quodl. 3, q. 36; De Veritate, q. 15, a. 2; ad Rom. 2, 14-18.

31. The eternal law, existing in the divine mind, most perfectly exhibits the order of things. The natural law, which is an application of the eternal law, exists in the human mind. Wherefore the natural law, by the very fact that it is manifested through human reason, falls short of the supreme perfection of the eternal law. Hence it happens that what we think and judge, in more difficult matters, does not always answer to the rules of the divine mind, and remains obscure and unknown to us. Hence that thing, although materially and in itself it pertains to natural law, nevertheless does not pertain to it formally and as regards us, since it has not been sufficiently promulgated to us by the natural light.

32. Can boys invincibly be ignorant of the malice of pollution? - Reply. Affirmatively, speaking absolutely, at least in some rare case, and at the beginning of a depraved custom. The reason is that the fact that an immodest look or touch, or the seeking of pleasure from pollution procured, or even naturally arisen, etc., is morally evil and illicit, is not made known so evidently from the very comprehension of the first principles; rather, reasoning is needed in order to detect their malice. Therefore their malice can, at least for some time, be inculpably unknown. From this the prudent confessor will easily conclude that, in such a contingency of fact, one must proceed cautiously and prudently; and this caution and prudence, if it is to be observed with all especially in the matter of chastity, is to be observed most of all with boys and girls. - Elbel 128; Struggl, loc. cit., n. 13.

What is certain conscience; and what is its directive force? - Certain conscience properly is that conscience which rests upon a certain motive; and consequently judges concerning the honorableness or shamefulness of the action to be done without fear of erring. Less properly, however, it is that which judges simply without any fear of erring concerning the honorableness or shamefulness of an action. This latter is only subjectively certain; the former is also objectively certain. It can likewise be certain strictly and broadly, or morally. Strictly certain excludes every doubt, both prudent and imprudent. Broadly or morally certain excludes only every prudent doubt. Its directive force is declared by the following propositions.

It is unlawful to act without conscience subjectively certain concerning the honorableness of the action. - Proof. He who acts without this conscience wills an action concerning whose honorableness or shamefulness he is uncertain. But to will an action concerning whose honorableness or shamefulness someone is uncertain is nothing other than to will it whether it is good or evil. But again, to will an action whether it is good or evil is illicit; for this is a will consenting to evil. Therefore. S. Th. 1. 2. q. 19. a. 3. 5, Quodl. 3. a. 27 ad 2, Quodl. 8. a. 13; L. 1. 1. n. 3; Suarez tr. 3. d. 12. s. 3; E. M.

Note: 1. Sin, precisely because it is against conscience, does not have a special malice, unless it is done so that conscience may be conquered. The first reason is because this is intrinsic and common to every sin, that it is against conscience. The second reason is because then there is had a directly willed contempt of the rule of every good operation, and thus someone exposes himself to the danger of all crimes, which, as is clear, is a special and most grave disorder of the will, against the natural inclination of the will toward good. - Lessius on q. 19. a. 6. d. 3; S. Th. 2. 2. q. 14. a. 1. 4.

2. Likewise it is a special sin if someone sins from certain malice through contempt, by casting aside and removing that which could impede the election of sin; and it is a sin against the Holy Spirit. - Six species of this are enumerated: desperation, presumption, impenitence or the resolve not to repent, obstinacy or the resolve to cling to sin, attacking acknowledged truth so that one may sin more licentiously; envy of fraternal grace, by which someone envies not only the person of his brother, but also the grace of God increasing in the world.

Only conscience subjectively certain is the rule of morals. But morally certain conscience suffices. Proof of the 1st part. For, as is clear from the preceding proposition, n. 100, without this conscience no one can act. Besides this conscience no other subjectively more perfect conscience is given. Therefore with this alone can someone act; and therefore this conscience alone is the rule of morals. Proof of the 2nd part. 1. From the common opinion of doctors and universal practice. 2. Because most often another certainty cannot be had; and no one necessarily sins. 3. Because, while this moral certainty stands, someone acts prudently, for moral certainty, although it does not exclude every doubt, both prudent and imprudent, nevertheless excludes every prudent doubt. Therefore. Rom. 14:23; C. Litteras 13 de Restit. spoliat.; S. Th. 2. 2. q. 70. a. 2.

It is lawful to act according to a certain conscience which is nevertheless invincibly erroneous. - Proof. He who acts in this way wills, as much as is in him, a good action, and consents only to a good action. But it is right to will this action. Therefore. The major is proved, for nothing is willed unless first known. Therefore, while an invincibly erroneous conscience stands, he who acts according to it wills, as much as is in him, a good action, and consents only to a good action. - L. 1. 1. n. 5; Elbel 126.

It is unlawful to act against a certain conscience which is nevertheless invincibly erroneous. - Proof. He who would act in this way would will an action which he judged prohibited; he would not will one which he judged commanded. But it is unlawful to have this will, because it is a will consenting to evil. Therefore. "It must be said that simply every will discordant from reason, whether right or erring, is always evil." S. Th. 1. 2. q. 19. a. 5, 2. D. 39. q. 3. a. 3, Quodl. 3. a. 27; L. l. c.; Cajetan on 1. 2. q. 19. a. 5; Suarez tr. 3. d. 12. s. 4.

It is lawful to act according to a certain conscience, even though vincibly erroneous. - Proof. Because when the action is judged honorable or shameful with certainty, the will acting according to this conscience pursues the honorable and flees the shameful, which is altogether licit. But that this conscience is vincibly erroneous does not make it so that, when someone actually acts according to it, he sins; rather, it makes it so that the fault is only in the cause, whence also it is that judgment about its gravity or lightness must be made not from the grave or light effect, but from the grave or light negligence in seeking the truth. Now when someone actually acts, if in no way does he attend to the erroneous conscience which he has, and has no suspicion about it, since by hypothesis the conscience is certain here and now, he is already acting not from a vincibly erroneous conscience, but from an invincible conscience. La-Croix l. 1. n. 42. 43. 757. 760; Kenrick ed. 2. Mechl. 1860. n. 36.

It is unlawful to act against a certain conscience which is nevertheless vincibly erroneous. - Proof. Because then someone would act against a certain judgment; and would will the action which he judges prohibited, and would not will the action which he judges commanded; which will is evil, for it is affected toward evil. Therefore. S. Th. 1. 2. q. 19. a. 5. 6; Suarez tr. 3. d. 12. s. 4; Elbel 122. 137. 138; L. 1. 1. n. 4; La-Croix l. 1, n. 42. 43. 757. "And therefore it must be said that every conscience, whether right or erroneous, whether in things evil per se or in indifferent things, is obligatory; so that he who acts against conscience sins." S. Th. Quodl. 3. a. 27, Quodl. 8. a. 15.

Note: "A sin committed against conscience has its species from the particular matter in which it is thought to be concerned; or from order to the particular precept which it is thought to oppose. For example, if you think the thing which you take is not yours, yet in fact it is yours, it will be the sin of theft; if you think it is against the obligation of a vow, it will be the sin of sacrilege. The reason is that sins receive species from the object either of the external action or of the will. Nor does it matter whether this object is evil in reality, but whether it is apprehended as evil, because the will is borne toward it according as it is proposed by reason." Lessius on q. 19. a. 6. d. 3; S. Th. 1. 2. q. 19. a. 5 ad 3.

Can someone labor under an invincibly erroneous conscience as regards depraved desires and other merely internal acts, namely if no exterior action follows? - Speaking explicitly and generally about desire, Elbel has this, n. 127: "That many, at least among the more uneducated and less instructed, can inculpably persuade themselves that desires of this kind are not evil unless they are completed by deed, seems sufficiently certain; and Sanchez, Stoz, and La-Croix expressly teach this." This opinion, says S. Alph. 1. 1. n. 9, "I have never been able to judge probable.... With other learned recent authors I judge it little probable." The reason for this opinion is that if someone certainly knows the malice of the external action, and nevertheless wills to execute it, he already knows that he wills evil. How then will he be excused from sin? But as regards simple delectation, that invincible ignorance can more easily be present; for the tendency of the will toward evil is not so evident as in desire efficacious of itself. And the same also seems to have to be said of inefficacious desire.

Can there be an invincibly erroneous conscience concerning the precepts of natural law? - "It is certain that in the first principles of natural law, as also in the proximate conclusions and certain obligations of one's own state, invincible ignorance is not given, because by the very light of nature such things are known to all, except to him who closes his eyes lest he see them.... On the contrary, however, the unanimous opinion of theologians is... that in mediated and obscure conclusions, or those remote from the principles, invincible ignorance is indeed given and must be admitted." L. 1. 1. n. 8. 170 seq.; Struggl tr. 3. q. 1. n. 10-13; S. Th. Quodl. 3. a. 36, De Verit. q. 17. a. 2; De Malo q. 3. a. 8; Rom. 2:14. 15. In the first principles of natural law, for example: good is to be done, evil avoided; the highest good is to be loved, evil detested; what you do not wish for yourself, do not do to another; thanks are to be given to benefactors, etc. In proximate conclusions, for example: God is to be worshiped, parents are to be honored, theft is not to be committed, etc. In remote conclusions, for example: private revenge is not to be exercised, abortion is not to be procured, etc. Eternal law, existing in the divine mind, most perfectly exhibits the order of things. Natural law, which is the application of eternal law, exists in the human mind. Therefore natural law, by the very fact that it is manifested through human reason, falls short of the highest perfection of eternal law.

Hence it happens that not always what we think and judge, in more difficult matters, corresponds to the rules of the divine mind, and remains obscure and unknown to us. Whence that thing, although materially and in itself it pertains to natural law, nevertheless does not pertain formally and as regards us, since it has not been sufficiently promulgated to us by the natural light. - Wirceburg. De Actib. hum. c. 1. a. 3.

Can children invincibly be ignorant of the malice of pollution? - R. Affirmatively, absolutely speaking, at least in some rare case, and at the beginning of a depraved habit. The reason is that the fact that an immodest look or touch, or the capturing of pleasure from procured pollution, or even from that which has naturally arisen, etc., are morally evil and illicit, is not so evidently made known from the very comprehension of the first principles, but discourse is needed to detect their malice. Therefore their malice can at least for some time be inculpably unknown. From this a prudent confessor will easily conclude that in such a contingency of fact one must proceed cautiously and prudently; and this caution and prudence, if it must always and with all be observed, especially in the matter of chastity, must be observed most of all with boys and girls. Elbel 128; Struggl l. c. n. 13.

39. • DEFINITION. Certain conscience is that by which someone firmly and without fear of erring judges that something is good or evil.

DIVISION. Certitude is usually distinguished as threefold:

1. Metaphysical, which belongs to those propositions in which the attribute belongs essentially to the subject, and therefore is immutable.

2. Physical, which is founded on the constant order by which the world is ruled; this stands firm as long as physical laws are constant, and are considered to have been constant.

3. Moral, which rests upon the laws by which men are ruled in their acts.

Again moral certitude is subdivided into perfect and imperfect. The former is that which is so founded on moral laws that it is clearly perceived that the proposition cannot be false. This is mediately reduced to metaphysical certitude. The latter is that which belongs to those propositions in which it is not absolutely repugnant for error to be present, although it could happen only with the greatest difficulty. This admits various degrees.

Likewise some certitude is direct, which is obtained through certain arguments intrinsic to the matter; another is indirect, which is had from some extrinsic principle, for example, the authority of the Church.

Principles. - I. Certain conscience alone is the right rule of morals. The reason is 1. because everything which is not from faith is sin. Rom. 14. 23; 2. because one acting with a conscience not certain violates the obligation of inquiring into the truth, and therefore sins formally ¹.

¹ Namely, precepts oblige us not only not knowingly to violate them, but also not to transgress them through negligence in inquiring. And from this is the guilt of him who acts while doubting about the honesty of the act. Concerning this matter Suarez (On Censures, disp. 40, sect. 5, no. 12): As long as man does not do what is in him to lay aside doubt, whatever of danger there is in such an operation is imputed to him; for the ignorance which intervenes there is vincible, and therefore cannot excuse from fault. Hence not even he is immune from this fault who, while acting rashly, embraces that part which agrees with the right norm of acting.

II. Morally certain conscience, even imperfect, suffices. The reason is 1. because one acting with such a conscience truly acts from faith; - 2. because absolute certitude often cannot be had; - 3. because it is clear from the common opinion of the Doctors and from universal practice ².

² Whatever is lacking in a plainly firm certitude in the case is always supplied through reflex principles, as will soon be said where probable opinion is treated. For otherwise certitude concerning the honesty of the action must be firm, as below it will occur to note concerning the theories of the probabiliorists.

Florus, making a general confession, accuses himself that, while still a boy, he once or twice had had pollution, and had never confessed it, because at that time he did not think it a sin. He adds besides that, now as an adolescent, he shamefully looked at and touched his cousin, and that he confessed this only generally, omitting the circumstance of the cousin, which he did not think necessary. Moreover he says that he often nourished evil thoughts in his mind, but he did not confess them either, thinking for a long time that sin existed only in the work. Likewise he confesses that, having been called into court, although he had given an oath to tell the truth, he told a lie, yet he judged this altogether necessary for saving a friend from a long and hard imprisonment. Lastly, he confesses that, laboring under a grave illness for a year and more, he omitted Mass and did not observe abstinence and fasting.

Q. 1. What is erroneous conscience, and can one follow it? 2. Whether and how did Florus sin?

R. To the first, cf. I. M. 98 seqq. To the second: Florus could absolutely, in boyhood, have been ignorant at first of the malice of pollution. Therefore, if in good faith he did not confess that sin because he had no consciousness of sin, he does not seem to be disturbed. I. M. 110.

Likewise he does not seem to be disturbed on account of the omitted circumstance of the cousin, whose special malice of incest he could more easily have been invincibly ignorant of. But this circumstance changes the species in itself with respect to touches, by no means with respect to looks. I. M. 784.

With respect to evil thoughts, good faith and invincible ignorance are admitted with more difficulty. Nevertheless, if Florus affirms that he was ignorant of this sin of thoughts, the confessor must indeed attend and investigate what kind those thoughts were, and whether Florus believed that from a culpably or inculpably erroneous conscience. For if, after prudent investigation has been made, from the rudeness of Florus his good faith appears, he does not seem to be disturbed in this either with respect to past confessions; but he is only to be instructed if he is still in error. For this must besides be attended to here, that good faith and ignorance can also be rather in fact than in law, that is, it can rather be concerning the consent given to the thoughts than concerning the very malice of evil thoughts, if consent accedes to them. I. M. 108.

From the fact that Florus judged a lie necessary for saving his friend, it does not truly follow that he erred in good faith and by invincible ignorance. Therefore Florus is to be questioned further, since it is a matter of grave perjury because of the added oath: whether in fact he thought that he could then lie, indeed perhaps even that he ought to because of the enormous danger in which his friend was placed.

Lastly, Florus did not sin by omitting Mass while held back by grave illness, since a necessity of sinning is not given. The same must be said of abstinence and fasting not observed for the same reason of infirmity; and although perhaps he omitted Mass and abstinence and fasting when he was already beginning to recover, it indeed seems difficult that he truly persuaded himself that he sinned gravely in this matter, if he had still not in fact recovered sufficiently. - Elbel 124-133; G. 37-42; I. M. 98 seqq.

354. 1. Notion. Here we treat of lax conscience, especially insofar as it denotes a habit, or a disposition of soul which inclines reason to diminishing or denying moral obligations, and therefore to extending liberty too much. By force of this habit, in a particular case, conscience judges, without sufficient reason, that something which is truly prohibited is licit, or that what is grave is a light sin. - Sometimes, from a long-standing habit of sinning, the moral sense is so clouded that conscience thinks little or nothing of even very grave sins, calling evil good, and drinking iniquity like water:¹ then it is called seared.²

² Bourdaloue excellently explains its causes and dangers, Sermon pour le 3e Dim. de l'Avent, sur la fausse conscience; cf. Vieux Moraliste, apud Ami du Clergé, t. XXIV, 1902, p. 737-743.

¹ Isa., V, 20; Job, XV, 16.

² 1 Tim., IV, 2.

355. 2. Causes. Among the causes which form a lax conscience, these can be numbered: (a) depraved education: for those who from infancy have been instructed not in the law of the Lord, but in worldly corruptions and false opinions, and have had before their eyes examples of all vices, easily are ignorant of not a few precepts of the natural law, and judge as indifferent certain acts shameful and dishonorable in themselves; (b) defect of consideration and counsel: those who do not think before acting, and in more difficult matters do not seek the counsels of the wise, are often deceived, and hold as good or at least indifferent what is truly evil; (c) the impulse of desires: namely, when various passions urge, reason is not rarely clouded: what we vehemently desire appears licit; whatever we will is good, and whatever pleases is holy; movements of anger seem to be nothing other than pious indignation, - unbridled ambition nothing other than noble emulation, - avarice is held as legitimate foresight, - commercial frauds are judged an exhibition of industry, etc.; (d) the habit of doing evil: for, sins having been multiplied, the moral sense is dulled, fear of God and reverence for law gradually vanish; hence those things which at the beginning were judged very grave crimes are soon considered as light or no delicts; (e) presumptuous trust in God: God, they say, good and merciful, will forgive us; for He has known our frame and the infirmity of human flesh; wherefore He is much more inclined to benignity than theologians and preachers, nor does He so strictly reprove what moreover is done by most.

356. 3. Harms. Lax conscience, like the ignorance upon which it rests, can be vincibly or invincibly erroneous, according as it can be corrected by moral diligence having been applied or not, according to what was said above, n. 90-98: yet each is full of dangers.

(A) Even when conscience is invincibly erroneous, it induces many evils;¹ for it is the cause why many acts sinful in themselves and objectively are perpetrated. Now an objectively evil act: (a) is a disorder, since it is opposed to the law which is an ordination of reason, and therefore of itself, without the formal malice of the agent, gradually depresses the moral sense, and, when it is often repeated, generates habits evil of themselves and very harmful; thus he who, even from ignorance, often acts against truth or chastity, even if he does not formally sin, commits something shameful and dishonorable in itself, which gradually dulls his moral sense; (b) it gives scandal: for many, seeing evil acts often committed by others, from this take occasion of sinning, and easily persuade themselves that those acts are not very depraved, indeed perhaps even licit, since they are done daily by so many men; from this, gradually and imperceptibly, morals are corrupted, with great detriment to private persons and to the whole of society; (c) it induces the danger of sinning formally: for by acts against the law often repeated, even ignorantly, habits of themselves vicious are soon acquired; and, when afterward conscience awakens, and their malice clearly appears, they are not easily eradicated; thus one incurs the danger of formally consenting to acts which are now apprehended as evil.

¹ This is clearly explained by Vieux Moraliste, apud Ami du Clergé, t. XXI, 1899, p. 1169-1175.

357. (B) But often lax conscience is vincibly erroneous, and therefore culpable, because it was voluntarily formed, insofar as the agent, entangled in the snares of the passions and burning with pleasure, desired and suggested to himself, while conscience resisted, that this or that action was not prohibited, and afterward suffocated the remorse of conscience; or because, doubting or at least suspecting that the matter was evil, nevertheless he was unwilling to take counsel, lest perchance he discover the truth and no longer be able to enjoy the intended pleasure.² Then indeed he sinned formally, and indirectly or in the cause willed the depraved effects which he foresaw would follow therefrom (above, n. 97 and 171-174).

² If it is actually vincibly erroneous, by that very fact it is not certain, and therefore not to be followed, as is declared below.

Moreover if, at the very time at which he acts, someone doubts or suspects that the matter is evil, and moreover knows that his conscience is lax, he cannot follow it, because he is conscious that it is not a right rule of morals, but is held to reform it by the means soon to be set forth. Wherefore by following it he voluntarily exposes himself to the danger of sinning, and therefore actually sins.

By these grave sins often committed the way is prepared for blindness of mind and hardness of heart: for the intellect is clouded insofar as it has become accustomed to approving false things as true, evil things as good; and the will is hardened in evil, insofar as, by indulging pleasure, it acquires a vehement propensity toward depraved acts, so that it obeys conscience only with difficulty.

358. 4. Remedies. As soon as someone becomes conscious that he has entered the way of laxity, he ought seriously to strive, under the guidance of a prudent confessor, to reform his conscience.

(a) First of all he will have recourse to prayer, so that, helped by divine light, he may attain practical knowledge of the rule of morals, - and, relying on divine help, may be able not only to hear, but also to follow the voice of right conscience, notwithstanding human infirmity: "Give me understanding, and I will search your law, and I will keep it with my whole heart."¹ (b) Afterward there is required the agent's own consideration before acting, with a sincere will of knowing and doing what is honorable, and not what pleases; but to discover the truth more easily, let the counsels of skilled and honorable men be sought, and not those of men who are easily deceived by the fallacies of the age; (c) finally let the impediments be removed, namely disordered passions and vicious habits, by which conscience is frequently clouded.

¹ Ps. 118, 34.

But the confessor should receive with paternal affection those who seriously wish to be amended, even if for a long time they have walked in broad ways; and he should instruct them rather than rebuke them, - he should add courage to them, and persuade them that the reformation of conscience, although difficult, is in no way impossible, provided that prayer is joined to good will and assiduous efforts.

367. 1. Preliminary remarks concerning certitude. Certitude in general is the firm adherence of the mind to some notion or fact, without fear of erring. By reason of the foundation on which it rests, certitude is distinguished as threefold: (a) metaphysical, which is founded in the very essence of things and ideas; thus we are metaphysically certain that the whole is greater than its part, because the truth of this proposition clearly shines forth from the very comparison of the ideas; (b) physical, which is founded in the constancy of natural laws; thus we are physically certain that fire burns, because from constant experience it is established for us that there is in fire the power of burning; (c) moral, which rests on the constancy of the laws of the moral order, or on the common manner of acting of free beings. This is: speculative, if it concerns abstract truths or the liceity of an action in general; and practical, if it concerns the liceity of an action to be placed here and now.

368. 2. Concerning the certitude which belongs to conscience. (A) Now the certitude which belongs to the practical judgment of conscience is moral and practical certitude: for since it pronounces concerning the liceity of such or such an action, not in general and in the abstract, but in the individual and in the concrete, with attention given to all the circumstances, the judgment brought forth is not infallible, but rests on human prudence,¹ which can be mistaken.

¹ Not a few theologians say that conscience sometimes enjoys absolute certitude, because it is founded on a motive altogether infallible; such, they say, is the certitude which is had concerning the precepts of the Decalogue and their proximate conclusions. - But in speaking thus they confuse synderesis or moral science with conscience: for this latter does not judge concerning the precepts of the Decalogue, but concerning the practical question whether such or such an action, in these or those circumstances, is prohibited by the Decalogue or not.

(B) Practical certitude itself admits several degrees: (a) sometimes it excludes every doubt and every fear of erring, and is called strict moral certitude; this can be had with regard to practical judgments altogether evident, for example, here and now I ought to abstain from such a theft; (b) sometimes, however, there is had only practical certitude broadly so called, or prudential certitude, which does not exclude every doubt, but only prudent doubt; thus, for example, we are not absolutely, but only prudently, certain concerning the validity of baptism or of orders received: for it can happen that the minister lacked the required intention; wherefore we have some fear of erring, but that fear, as being slight, does not destroy prudential certitude. This suffices in the moral matter, since often we cannot have another; now reason itself dictates to us that that certitude suffices which is accommodated to the infirmity of human nature; otherwise man would frequently remain perplexed, not knowing what was to be done.

369. (C) But this practical certitude, taken strictly or broadly, can be acquired in two ways, directly or indirectly: (a) directly, when, from the very comparison of the action with the law, we come to a morally certain conclusion; thus, given the law of hearing Mass on a feast day, unless a grave inconvenience is present, I judge morally certainly that I am held by that precept, because I see here and now that in my case there is not a grave inconvenience; (b) indirectly, that is, either from authority, or from an external, or reflex, principle, as they say, when we cannot come to a certain conclusion unless a certain principle extrinsic to the thing itself is called into the middle; thus a judge, after attentive consideration of the proofs brought forward in a criminal case, sometimes doubts whether the accused is truly culpable; then he has recourse to an external, or reflex, principle: in doubt, favor is to be shown to the accused; and therefore practically and morally certainly he concludes: this accused man, all things considered, is to be absolved. - That external principle can be the judgment of a prudent man, and especially of a confessor.

370. (D) Certain conscience is not always true, as we have already noted, but can be erroneous, since one can err even when he prudently judges concerning the liceity of some action: then it is called invincibly erroneous, according to the things said above, where we treated ignorance, n. 92. If conscience is actually vincibly erroneous, by that very fact it is not morally certain; for in this case the agent can expel the error, or at least prudently doubts concerning the liceity of the action here and now to be performed. But it must be said otherwise of conscience previously vincibly erroneous, but which at present is actually invincibly erroneous, because namely the agent does not think about the necessity of inquiring: for this is now morally certain, because, although previously he had thought about the necessity of investigating the truth, now he prudently thinks the action to be licit, without suspecting that the matter must be further investigated. Thus a seminary student, while he was studying theology, foresaw that from his negligence he would give certain erroneous decisions: then his conscience was vincibly erroneous; afterward, however, having forgotten this negligence, he brings forth a false judgment concerning a matrimonial case, without at that instant suspecting that he errs: his conscience is invincibly erroneous, and subjectively morally certain.

371. 1. Principle: Conscience morally and practically certain, and indeed it alone, is the proximate rule of morals.

(A) Conscience morally and practically certain is the proximate rule of human actions. For conscience morally and practically certain, in whatever way this certitude has been acquired, is that which, without prudent fear of erring, judges that some action is licit or illicit, obligatory or permitted; but it cannot happen that he sins who is prudently certain that the action which he does is honorable, or that the one which he omits is illicit. For no action or omission is imputable to anyone unless it is voluntary; but the malice of an action is not voluntary unless it is apprehended as such by the intellect; therefore he does not sin, but acts rightly, who follows a morally certain conscience; therefore this is deservedly called the proximate rule of morals.

372. (a) Concerning this there is assuredly no difficulty when certain conscience is at the same time true: for then it is altogether consonant with the ultimate rule of morals, namely divine reason. - But the same thing must be said even when certain conscience is invincibly erroneous, because, although it disagrees with the law, the defect of conformity is not imputed to the agent, because it is invincibly unknown by him; and therefore an act elicited according to an invincibly erroneous conscience is objectively and materially evil, as often as namely it is opposed to a law commanding or forbidding, - but subjectively and formally good, because it is apprehended and intended as such. - The same thing must be said of conscience here and now invincibly erroneous, which antecedently was vincibly erroneous. For an act placed according to such a conscience not only is materially evil, but can also be called formally evil in its cause (above, n. 97). Nevertheless it is not in itself actually evil: for it is elicited in good faith, and is not apprehended nor intended as evil: "Every human act has the character of sin or merit insofar as it is voluntary; but the object of the will according to its proper character is the apprehended good: and therefore a human act is judged virtuous according to the apprehended good toward which the will is borne of itself, and not according to the material object of the act."¹

¹ St. Thomas, Quodlibet., III, a. 27; cf. I-II, q. 19, a. 7; q. 76, a. 3.

This can be confirmed from proposition 28, condemned by Alexander VIII, 7 December 1690, at least as rash:² "Although invincible ignorance of natural right be given, this, in the state of fallen nature, does not excuse the one acting from formal sin itself"; therefore invincible ignorance, and consequently invincibly erroneous conscience, excuses from formal sin.

² Denzing., n. 1159.

373. (b) This holds even when moral certitude is only prudential, and was had by the aid of a reflex principle. For since the question is concerning things to be done, that certitude suffices which can be obtained in practice; now, when the question concerns performing or omitting such or such an action, not rarely only prudential certitude can be acquired. Sometimes speculative doubts arise which it is impossible to solve directly; from another side the necessity of acting presses; therefore nothing remains except to solve the speculative doubt practically by the aid of some reflex principle (above, n. 369). Thus he who, after all things have been diligently weighed, follows the prudent dictate of conscience, acts rightly before God.

374. (B) Certain conscience alone, morally and practically certain, is the right norm of actions. For he who acts with conscience which is not practically certain, by that very fact voluntarily exposes himself to the danger of transgressing the law, since he prudently and practically doubts whether the action, here and now to be placed, is licit; moreover, he who voluntarily exposes himself to the danger of sinning, while he can easily avoid it, by that very fact implicitly wills to sin. Therefore he who practically doubts concerning the liceity of an action here and now to be performed cannot, while the doubt stands, proceed further, but ought to form for himself a practically certain conscience, by the aid of a reflex principle, according to the manner to be explained below.

375. Corollaries. (A) Conscience here and now vincibly erroneous is not a legitimate rule of acting. For, from one side, that conscience is not consonant with the objective rule of morals; and from the other, that defect, as being actually voluntary, is imputable to the agent; since, in this case, the agent prudently doubts concerning the liceity of the action, and therefore ought to inquire further, if he can, and put away the error. - But if he cannot, and from another side the necessity of acting presses, he ought to choose that part in which evil, or the greater evil, is more safely guarded against; for by acting thus, he puts aside the practical doubt, and the error is not imputed to him unto fault. But if he chooses that of whose liceity he practically doubts, by that very fact he sins, by rashly exposing himself to perpetrating evil.

376. (B) To discern whether the conscience of the penitent was vincibly or invincibly erroneous, the confessor will ask: (a) whether the penitent perceived some indecency in the act, or at least doubted concerning its liceity; (b) whether conscience dictated to him that the confessor or another prudent man was to be asked, and he voluntarily neglected the occasion of inquiring. If he sincerely denies both, the error was invincible; if he affirms either, the error must be called vincible. - But the nature and gravity of the sin committed from vincibly erroneous conscience depends on the very disposition of the agent at the time when he acts: if he apprehends the matter rather clearly as of great moment, and as contrary to this or that virtue, he sins gravely against that same virtue; but if the matter seems to him of slight moment, or its malice appears only confusedly, the sin will be venial. - From this it is clear how necessary it is for confessors kindly and prudently to explore the conscience and character of each penitent, so that they may form a true judgment concerning the sins committed by him.

377. Hence penitents are deceived who, after they have acted in doubt, seek in books or from a prudent man whether the action is licit, and lay aside every anxiety if they learn that the matter is not objectively evil: the morality of an action depends on the dictate of conscience brought forth at the very instant at which the action is completed, but not on the judgment which is afterward brought, when the matter has been better investigated. Whence that investigation will indeed be greatly useful for the future, but by no means for the past time.

To be entirely reliable, conscience must be right, certain, and watchful. Hence the three conditions for the normal functioning of conscience enumerated by the Schoolmen: rectitudo, certitudo, vigilantia. i. In order to be right (recta s. vera), conscience must accord with the eternal law. Every man is in duty bound to follow his conscience when it prescribes an act as commanded or forbids it as unlawful.

Conscience is called erroneous (conscientia erronea) when its dictates are not in harmony with the moral law.¹ The mistake may be owing to a false conception of the law (error iuris), or to a wrong application of its provisions to a concrete fact (error facti), or to a faulty conclusion formed with regard to the latter (iudicium facti).²

¹ Cfr. Rom. XIV, 23; 1 Cor. VIII, 7; X, 25 sqq.; John XVI, 2.

² Cfr. St. Thomas, De Veritate, qu. 17, art. 2: "Conscience is nothing other than the application of knowledge to some particular act. In this application error can occur in two ways: in one way, because that which is applied contains an error in itself; in another way, because it is not applied correctly. —Cfr. 1 Cor. VIII, 1-13.

If a mistake is made that could have been avoided, the conclusion is said to be vincibly erroneous (error vincibilis). In this case an act may be sinful, not because the agent has obeyed his conscience, but because the error was willed in the cause (voluntarium in causa). An er roneous conscience is invincible (error invincibilis) if the mistake committed was absolutely unavoidable. To follow the dictates of an invincibly erroneous conscience is no sin, even when the act performed is objectively evil. On the contrary, it would be sinful to act against one's conscience, even if, in acting against it, one would be objectively in the right. Of course, the mistake must be corrected as soon as it is realized.

2. Conscience is called certain (conscientia certa) if it declares without hesitation that an action is right or wrong. Where uncertainty exists, it is a duty to obtain certainty as soon as possible. When a man finds himself unable to form a certain conclusion with regard to the moral character of an act, he will either suspend judgment or assent to one of two contrary propositions, though conscious that the other may be true. In the former case, i. e., if no sufficient reasons are known for either affirming or denying a proposition, or if equally important reasons speak for the one and for the other, conscience is said to be doubtful (conscientia dubia). A doubtful conscience, if it bases its action on good and solid grounds, is called probable (conscientia probabilis).

A doubtful conscience may, therefore, be defined as a suspension of judgment with regard to the lawfulness of an act.

Theologians distinguish between positive and negative doubt. When there are no reasons, or very slight reasons, on either side, there is a negative doubt. Such doubts, which calm consideration generally shows to be unfounded, must be treated like temptations. When there is an apparent equality of reasons, and the mind cannot arrive at a decision either one way or the other, the existing doubt is positive. When positive doubt has reference to the morality of an action it is not lawful to perform that action.³ While conscience is in this state, one may abstain from action, or, if the decision cannot be postponed, one must do what would be licit in any case. Thus, in doubt whether an action be permissible, when it is certain that such an action may be omitted, the action is to be omitted, and vice versa. This is what is meant by the Scholastic axiom, "In dubiis pars tutior est sequenda.

³ Cfr. St. Alphonsus, Theol. Mor., l. I, n. 22 (ed. Gaudé, I, 11): "We say that it is never lawful to act with a practically doubtful conscience; and in the event that someone acts, he sins, indeed with a sin of the same species and gravity concerning which he doubts, because one who exposes himself to the danger of sinning already sins, according to the saying: He who loves danger shall perish in it (Ecclus. III, 27). Therefore, if he doubts whether it is mortal, he sins mortally."

From what has been said it follows that every man is in duty bound to rid himself of doubts and to acquire a certain conscience (bona fides). Whoever makes a sincere effort to solve his doubts by observing the conduct of conscientious people situated in similar circumstances, consulting an experienced guide, praying for light and trusting in Providence, will not sin, even if his final decision should happen to be wrong.⁴

⁴ Indirectly, according to Lehmkuhl, one may resolve a doubtful case by these reflex principles: (1) In doubt, the condition of the possessor is the better; (2) It must be seen upon whom the burden of proof falls; (3) For a certain law outside the matter of justice to be satisfied, a probable fulfillment positively proved suffices; (4) In doubts, one must stand for that for which the presumption stands; (5) In doubt, judgment must be made from what ordinarily happens; (6) A fact is not presumed but must be proved; but what by law ought to have been done is presumed in doubt to have been done, or done rightly; (7) In doubt, favors are to be enlarged and burdensome things restricted, that is, the more benign course is to be preferred; (8) In doubt, that which is least is to be held; (9) In doubt, the safer part is to be followed. —For an explanation of these rules, and some useful hints as to their application, see A. Lehmkuhl, S.J., Theol. Mor., Vol. I, 11th ed., Freiburg 1910, pp. 122-126.

3. A watchful conscience (conscientia vigilans) is one which asserts itself promptly and strongly under all circumstances. The quality of watchfulness is enhanced by a conscientious observance of all the commandments, by careful attention to the inner workings of conscience, and especially by regular daily examinations.⁵ A conscience thus trained becomes tender (conscientia tenera) and makes its possessor a conscientious man.

⁵ Cfr. Gal. VI, 4 sq.; Eph. IV, 26.

Continued disregard of the laws of God renders the conscience obtuse (cauteriata) and finally lax.⁶ a) A blunt or obtuse conscience fails to protest even against grievous sins. It is called sleeping, not dead, because conscience never dies, but always awakes again, even in the greatest criminals, either of itself or under the influence of grace, though often too late.⁷ Needless to say, every man is bound to keep his conscience from going to sleep. b) A lax conscience (conscientia laxa s. lata) is characterized by a tendency to deny or diminish obligations. It results from harboring wrong principles and leading a sinful life, and may be described as a frivolous conception of life and its duties.⁸ When a man's conscience has grown lax, his actions are morally equivalent to those performed in a state of vincible ignorance. A lax conscience is very hard to cure.⁹ There is really but one effective remedy for it, viz.: a thorough-going change of life. This is a drastic medicine, but unless it is applied promptly, the patient will succumb to delusions, grow impenitent, and incur eternal damnation.¹⁰

⁶ Cfr. 1 Tim. IV, 2.

⁷ Cfr. Mark IX, 43.

⁸ Cfr. Matth. XXIV, 38.

⁹ Cfr. Apoc. III, 15 sq.

¹⁰ Cfr. Ecclus. III, 29: "The sinner will add sin to sin."

READINGS.—Th. Slater, S.J., A Manual of Moral Theology, Vol. I, pp. 59 sqq. —Sabetti-Barrett, Compendium Theologiae Moralis, 27th ed., pp. 35 sqq. —A. Sweens, Theologia Moralis Fundamentalis, 2nd ed., pp. 319 sqq. —A. Tanquerey, Synopsis Theologiae Moralis, Vol. II, pp. 203 sqq. —W. McDonald, The Principles of Moral Science, Dublin 1904, pp. 188 sqq.

— Practically certain conscience is always to be followed. Wherefore whether it be speculatively true or erroneous, the action will in reality have the goodness or malice which conscience proposes.

This is clear from Genesis 20, 4-7, where the excuse of his ignorance which Abimelech alleged is approved by God, and from the passage of the Apostle, Rom. 14, 14. 22. 23, compared with 1 Cor. 8, 11, where St. Paul teaches that conscience is polluted because of an action which is falsely thought illicit. And the reason is, because by the will by which a Superior wills something to be observed, by the same will he wills that obedience be given to the one herald, designated by him and faithful of himself, through whom alone his commands are intimated. But conscience performs the function of such a herald. For the rest, since the object of the will is the action as it is proposed by the intellect, the act receives its species from the object, "not according to the matter of the object but according to the account of the object" (St. Th. Quodl. 3, art. 27).

Wherefore the sin committed against a right conscience and the sin committed against an erroneous conscience do not differ in species.

Yet the act must always be supposed human. Wherefore involuntary distractions will not be imputed to him who erroneously thinks those same things to be sins.

— What if the conscience of ignorance or error has been culpable?

If while acting, the unskilled man does not advert to his ignorance, he has an actually invincible conscience, which by following he cannot actually sin. Yet he will bear the consequences of the harmful action, if any were sufficiently foreseen in the prior fault.

If while acting he was mindful of his ignorance, he ought to have inquired concerning the matter or abstained from the action.

Yet what if the action is necessary and the opportunity of inquiring is lacking: suppose an ignorant priest, who alone comes upon a sick man for whom death is imminent. Then his ignorance is reduced to invincible, nor will the error be imputed to him, unless, from the office which he bears, he could easily have foreseen that these circumstances would occur.

If, with inquiry omitted, he does not abstain from the action, the ignorant man will sin whether he acts according to or against the dictate of his conscience. And by acting according to the dictate, he will sin by his negligence and will be guilty of the evils which he foresaw confusedly. But by acting against conscience, he will besides sin by the sin apprehended through actual conscience.

A vincibly or invincibly erroneous conscience will be judged both from the presumptions which the matter and the person permit (with attention paid to his piety and learning), and from fitting interrogations of the agent: a) whether he adverted to any indecency in the act; b) whether he doubted concerning the liceity of the action; c) whether conscience warned him concerning a grave or light obligation of inquiring.

— Practically certain conscience is always to be followed, with the imputation of error culpable in its cause nevertheless saved. Even one guilty of conscious negligence will sin more by acting against conscience commanding or forbidding than according to it. But a vincibly or invincibly erroneous conscience must be prudently estimated.

St. Thomas, de Verit., q. XIV; 2.2, q. 1, a. 4; q. 2, a. 1; q. 70, a. 2; St. Alphonsus, I, 20-39; ed. G., I, p. 11 ff.; Mazzotta, tr. I, disp. 1, q. 3, c. 1-5; Bardi, Discept. de consc., discept. 1, c. 9; disc. V and VI; Reuter, P. I, tr. 2, c. 2, n. 75; Panzuti, Theol. mor., I, tr. 1, 3 and 4; Vind. Alph. (ed. 2), n. 125; Lehmkuhl, I, n. 119.

We shall speak: 1. of the necessity of certain conscience for acting rightly; 2. of the manner in which doubtful conscience is laid aside.

For the sake of clarity it is useful to premise the doctrine of St. Thomas concerning the threefold state in which, with respect to a proposed truth, our mind can be placed: namely concerning the state of certitude, doubt, and opinion.

30. "Our intellect," says the Angelic Doctor, "with respect to the parts of a contradiction, is disposed in diverse ways. For sometimes it is not inclined more to one than to the other, either because of a defect of things moving it, as in those problems concerning which we do not have reasons, or because of the apparent equality of those things which move toward either part: and this is the disposition of one doubting, who fluctuates between the two parts of a contradiction. But sometimes the intellect is inclined more to one than to the other, yet that which inclines it does not sufficiently move the intellect so as to determine it totally to one of the parts; whence indeed it accepts one part, yet always doubts concerning the opposite: and this is the disposition of one opining, who accepts one part of a contradiction with fear of the other. But sometimes the intellect is determined to this, that it totally adhere to one part: ... and this is the disposition of one understanding principles... of one knowing... and of one believing" (de Verit., q. 14, a. 1).

Elsewhere (3 D. 23, q. 2, a. 2, sol. 1) he has these things: "When the reason which moves toward one part neither suffices for terminating the intellect, because it does not resolve conclusions into principles known of themselves, nor suffices for terminating the will, so that it seems good to it to adhere to that part, then a man opines that to which he adheres and the intellect is not terminated to one thing, because there always remains a movement toward the contrary: for he accepts one part with fear of the other; and therefore one opining does not assent. But when a man does not have reason toward one part more than toward the other, either because he has reason toward neither, which belongs to one not knowing, or because he has reason toward each, but equal reason, which belongs to one doubting: then he in no way assents, since his judgment is in no way determined, but he is disposed equally toward diverse things." In what sense one opining does not assent, he explains there immediately afterward: "One opining has thought without perfect assent, but he has something of assent, insofar as he adheres to one more than to another." Likewise in the Summa Theologiae (2.2, q. 2, a. 1): "Some acts pertaining to the intellect have firm assent without such thought; ... but some acts of the intellect indeed have unformed thought without firm assent, whether they decline to neither part, as happens to one doubting, or decline more to one part, but are held by some slight sign, as happens to one suspecting, or adhere to one part, yet with fear of the other, which happens to one opining."

These things having been noted beforehand, without difficulty the diverse notions concerning the state of certitude, doubt, and opinion are established.

31. On the state of certitude.

Notion. CERTITUDE can be defined: the firm adherence of the mind to some proposition, without fear of erring; or also with St. Thomas: "The determination of the intellect to one thing" (3 D. 23, q. 2, a. 2, sol. 3); and in other words: "The firmness of adherence of the cognitive power to its knowable object" (ibid., D. 26, q. 2, a. 47).

Division. 1. By reason of acquisition, certitude is divided into direct or indirect certitude.

Direct certitude is that which arises from proper and intrinsic principles affecting the thing itself. Thus it is directly and perfectly certain that children owe love to parents; for the certitude of this thing is sought from the very relation of cause which parents have toward children.

Indirect or reflex certitude is that which is obtained from principles extrinsic to the thing. Thus, for example, a son invincibly doubting whether a thing commanded by his father is lawful in itself or not, can arrive at a certain dictate with respect to lawfulness if he has recourse (or reflects) to the general principle: In doubt, one must stand for the superior. See n. 38, where there are more things.

2. By reason of firmness of assent, it is divided into absolute and moral certitude.¹

Absolute certitude is the assent of the mind on account of an infallible motive. On account of this sort of motive, such firmness is present in the mind that it excludes not only every fear of erring, but even the power of deliberately fearing. The following propositions, and propositions similar to them, introduce this certitude: the whole is greater than its part; bodies are heavy; the Roman Empire once existed.

Moral certitude (such as is understood here) is the assent of the mind on account of authority or grave reasons; so that there is no founded reason for doubting or fearing concerning the truth of the object. Such certitude arises, for example, from the testimony of two men who are worthy of faith. It does not indeed remove the possibility of doubting, but it actually excludes prudent fear of error.

Broad moral certitude. From this perfect moral certitude, or moral certitude properly and strictly so called, there plainly differs imperfect moral certitude, or certitude improperly and broadly taken, by which one indeed adheres to one part, but with a certain prudent fear of error. Therefore in this state there is indeed an assent of the mind, and thus it differs from the state of strict doubt (n. 32); but that assent is not firm, but fearful; and thus it differs essentially from moral certitude properly so called, and agrees with the state of one opining (n. 33). In other words: broad moral certitude excludes prudent and strictly so-called doubt, but admits prudent fear or hesitation.

This notion of imperfect moral certitude, or broadly so called - which is of the greatest moment in this matter - plainly agrees with the doctrine of St. Thomas and of the other principal doctors.

By the Angelic Doctor this sort of certitude is called "probable certitude, which," he says, "attains the truth in the greater number of cases, although in the fewer number it falls short of the truth"² (2.2, q. 70, a. 2); likewise "certitude of prudence" (2.2, q. 47, a. 9), or "certitude of opinion" (3 D. 23, q. 2, a. 2, sol. 3, ad 1). Blessed Albert the Great agrees (In Topic., l. 1, tr. I, c. 2). St. Antoninus agrees, who calls the same "certitude of probable conjecture," and says that it arises "from gross and figurative probable conjectures disposed more toward one part than toward another" (Summa Theol., P. I, tit. 3, c. 10, § 10). Likewise Gerson, who has these things: "In morals, Aristotle says that certitude is to be taken grossly and figuratively; this certitude does not remove every probability or opinion of the other part, although it inclines more to this or to that, which suffices" (de Contr., P. 2, prop. 13).

Lugo also rightly says (de Fide, I, n. 316): "We can distinguish two grades of moral certitude. The first is of certitude which we have described, namely that which excludes every prudent fear of erring, and this is proper moral certitude. The second is of less proper certitude, which does not exclude prudent fear, but only prudent doubt concerning that object, or a prudent judgment concerning the contrary object."

Finally St. Alphonsus teaches: "For forming the moral certitude of some opinion, it is not required that the authors holding the opposite still lack every reason, even a light one; but it suffices if that opinion, with all things weighed, appears so true that scarcely any appearance of truth remains for the contrary, or that the contrary does not seem sufficiently probable" (Diss. 1755, n. 52). In the Moral Work (I, 81; ed. G., I, p. 60) it is possible to read: "A most probable opinion, which is also called morally certain, speaking broadly however, does not exclude every prudent fear lest it be false; unlike an opinion or opinion strictly certain, which excludes every prudent fear" (I, 81; ed. G., I, p. 60). St. Alphonsus also understands this imperfect moral certitude, or broadly so called, whenever he says that an opinion certainly or notably more probable is "morally or quasi-morally certain," or "sufficiently certain." Therefore several authors are mistaken who teach that broad certitude also excludes prudent and reasonable fear of error, and consequently begets firm assent.

32. On the state of doubt.

Notion. Doubt in general, insofar as it is opposed to strict certitude, is the suspension of judgment or of firm assent.

Division. Doubt is distinguished in many ways:

1. By reason of assent or adherence, it is divided into strict doubt and broad doubt. Strict doubt is the suspension of all assent, or the fluctuation of the mind, on account of equal motives for either part of a contradiction. This alone is true, genuine, properly so-called, and prudently formed doubt, according to the doctrine of St. Thomas (cf. above n. 31) and of all philosophers.³ Broad and improperly so-called doubt consists in a certain prudent fear of the intellect imperfectly assenting to one part of a contradiction. This fear, which by St. Thomas is also called "doubting," namely in a broad sense, or "some doubt" (quodl. VIII, a. 13), arises either from this, that the motive existing for only one part is not plainly firm but only probable, or from this, that the motives for one part are certainly or notably graver, although for the opposite part there are also motives grave in themselves. Therefore this broad doubt accompanies the state of broad and imperfect certitude (n. 31), or the state of one opining (n. 33).

Note. Suspicion is reduced to strict doubt; it stands midway between doubt and opinion, insofar as the mind, led by a slight sign, inclines toward one part only, but by no means assents to it. So St. Thomas (above n. 31), with whom St. Alphonsus wholly agrees (H. Ap., I, 77).

2. By reason of the motive or foundation on which it rests, doubt is negative or positive. It is negative when no probable reasons occur on either side, but either none or only light ones. It is positive when for each side (doubt positive on both sides), or at least for one side (doubt positive on one side), there is present a grave motive sufficient for forming a probable conscience, although with fear concerning the opposite.⁴

3. By reason of the object, there is doubt of fact and doubt of law. Doubt of fact is concerned with the essence or existence of a thing. For it asks what is: whether, for example, such a pact has been added to a contract or not; whether such a decree has been duly promulgated; whether it has been abrogated; whether the present thing is the object or matter of the law or not: for example, whether this food placed before me is meat or not; whether I have satisfied the law, vow, penance, obligation of contract, etc. Doubt of law is concerned immediately and of itself with the law or the obligation of the law, and consequently with the honesty of the action; for it asks (although only theoretically and in general): what is to be done; whether it is lawful to confer a sacrament with such matter, to enter into a contract with such a pact, etc. (I, 41, 53; H. Ap., XVI, 142; XVIII, 35; XIX, 79; cf. VII, 67, where there are examples).

It must be noted here that doubt of law arises from some doubt of fact; for right arises either from the essence of the thing (for example, from the very nature of man), or from some positive act, for example, from a contract, from the decree of a legislator, etc.; and similarly it is removed by a fact, for example, by payment of a debt, by dispensation from a law, etc. But doubts of fact are more commonly concerned with matter falling under a law, since in these it is generally asked: whether a man is placed in such circumstances as demand the application of the law.

4. By reason of the mode in which the object is considered, doubt is speculative or practical. It is speculative when one doubts concerning the truth of a thing or proposition, concerning the objective honesty of an action: for example, whether that war is just or not; whether painting is servile work; whether Baptism conferred with distilled water is valid, and like things. It is practical when one doubts concerning the subjective honesty of placing an action, that is, when someone doubts whether in practice, and with all the circumstances in which he is here and now placed having been weighed, he can or ought to act; for example, whether it is lawful for me to serve as a soldier in such a doubtfully just war; whether on this feast day to paint; whether to baptize this boy with distilled water (I, 21, 25; Istr., I, 13; Conf. dir., I, 9).

As can be seen, speculative doubt is a doubt of science, which proximately and of itself is concerned with the true, although consequently and remotely, when a moral matter is in question, it also regards the lawful. Practical doubt is a doubt of conscience, by which it directly and immediately regards the lawful. But it arises from speculative doubt, whether of law or of fact, and always supposes it: for no one, unless he is scrupulous, can doubt whether it is lawful for him, for example, to paint on a feast day, unless he has already doubted whether painting is servile work prohibited by God. Therefore speculative doubt is about the premises, practical doubt about the conclusion (Diss. 1757, n. 54).

33. On the state of opinion.

Notion. Opinion is a weak assent by which the intellect is borne toward one part of a contradiction, esteemed as true, with fear concerning the opposite.

It is said: 1. It is assent, and thus it differs from strict doubt and suspicion.

2. Weak, and thus it differs from strict certitude.

3. Esteemed as true; for "one opining," says St. Thomas (in VI Eth., lect. 8), "says that what he opines is true," and indeed he says this with fear. Accordingly, opinion also involves positive knowledge, although imperfect.

4. With fear, that is, prudent and reasonable fear; for imprudent and irrational fear is not always absent even from the certitude of faith.

And so the state of one opining, into which someone comes after mature consideration, includes broad doubt (n. 32), and coincides with broad and imperfect moral certitude (n. 31).

34. Note. The word opinion, as is clear, is taken here for the subjective state of the mind, but not for some opinion or objective proposition, in which sense we speak of an opinion, that is, a true, false, probable, lax, safe, etc., opinion or proposition.

These things having been noted beforehand, let us approach the argument of the present article.

35. Definitions. Certain conscience is that by which one firmly and without fear of erring judges that something is lawful or unlawful for him.

It differs from true conscience as certitude differs from truth. Truth regards the object, which is apprehended as it is in itself; therefore it excludes error. Certitude regards the subject judging that something is true without fear of falsity; therefore it excludes fear of error, which nevertheless can be present in the subject per accidens invincibly. Hence it is clear that conscience can be certain without being true. Yet of itself certain conscience is always right conscience; whence the question is always made only concerning certain conscience (Beaudouin, q. 2, a. 1).

Doubtful conscience is that which suspends assent for either part of the doubt, and remains uncertain and hesitating (I, 20).

It is clear that conscience of this kind, on account of the defect of judgment, is not conscience in the true sense of the name, but is called by this name improperly, and only from the usage of the schools.

36. Principles. I. For acting licitly there is required moral certitude concerning the honesty of the action. In other words, certain conscience alone is the rule of morals, and it is never lawful to act with a practically doubtful conscience (I, 55; H. Ap., I, 31). It is proved, 1. From the words of St. Paul (Rom. 14:23): Everything that is not from faith is sin. "It is said from faith, namely from the certain dictate of conscience, so that a man has persuaded himself in his conscience that by acting he acts rightly, as St. Chrysostom, St. Ambrose, and others with St. Thomas explain that phrase FROM FAITH." 2. From reason: he who acts with a conscience not certain voluntarily exposes himself to the danger of sinning, and by this very fact sins. And indeed, he who, uncertain about the honesty of an action, nevertheless acts, implicitly and interpretatively says: I wish to do this, whether it is lawful or unlawful: which is a virtual contempt of the divine law, and consequently sin (cf. St. Thomas, de Verit., q. 17, a. 3).

But if it is asked what sin one thus doubting and acting commits, St. Alphonsus answers (I, 22): "He sins, and indeed with a sin of the same species and gravity concerning which he doubts; because he who exposes himself to the danger of sinning already sins, according to that: He who loves danger shall perish in it (Ecclus. 3:27). Wherefore if he doubts whether that is mortal, he sins mortally." Cf. however n. 337, q. 2, where there are other useful things.

37. II. For acting licitly, ordinarily strict moral certitude is not required, but broad moral certitude suffices. This is the very common opinion among the authors. Cf. Dissertation de Usu moder., 1757, n. 31.

We say ordinarily, for sometimes prudence does not permit even the slightest danger of error to be undergone: for example, when the life of a man is in question, or the validity of Baptism to be conferred, etc.; in these cases certitude entirely strict is required, as we shall say more accurately in its place (cf. n. 81 ff.).

The reason is that, since God does not command impossibilities, those dictates in the matter of morals must suffice which we can practically form. But although we have strict certitude regarding first principles and their proximate conclusions, nevertheless ordinarily only dictates of broad moral certitude are at hand for us relative to remote conclusions.¹ Whence St. Thomas (2.2, q. 47, a. 9, ad 2): Certitude is not to be sought in the same way in all things, but in each matter according to its proper mode. But because the matter of prudence is singular contingents... the certitude of prudence cannot be so great that all solicitude is removed. And in another place: Moral matter is such that perfect certitude is not fitting (1.2, q. 91, a. 3, ad 3). To the matter also St. Antoninus (Summa, P. I, tit. 3, c. 10): It belongs to the disciplined man to seek certitude in each thing according to the exigency of the matter. Recall what we said above (n. 31). Cf. Suarez, de Lege, l. 8, c. 3, n. 19; de Relig., tr. 6, l. 4, c. 5, n. 5; Valensise (super syst. Theol. mor. disquisitio), where he treats the mind of St. Thomas concerning the sufficiency of probable certitude in moral judgments.

Note. Arguments of this kind, which establish the sufficiency of broad moral certitude, can be called concomitant principles. For they accompany, at least implicitly and in exercise, the direct arguments from which firm security cannot be had, so that they may render it plainly firm and perfect.

Nor is there an obstacle in the fact that in broad moral certitude there is still a certain prudent and founded fear of error (n. 31), for this remains only in the speculative order; but practically the fear of sinning is excluded by those same concomitant principles, which for this reason are also called by others indirect and reflex principles. Cf. Vind. Alph., Apologetic Dissertation, n. 125; Beaudouin, p. 44.

38. III. For acting licitly, reflex certitude sometimes suffices.

It is said: sometimes, namely if, while an invincible speculative doubt remains, direct certitude cannot be had. For before all things direct certitude is to be sought; that is, before all things diligent inquiry into the truth is required, because, as the doctors say: "The law of acting imports the law of knowing." But if, after sufficient inquiry, direct certitude cannot be obtained, indirect or reflex certitude suffices (I, 25).

It is proved, 1. From authority. "It is certain and commonly explored among all the doctors," says St. Alphonsus (I, 64), "that the moral certitude of some opinion, if it is not proved from some certain direct principle, is nevertheless proved from another reflex principle, likewise certain, as is proved from can. 4: Quid culpatur, caus. 23, q. 1, where St. Augustine writes: A just man, if perhaps he serves as a soldier even under a sacrilegious king, can rightly wage war when that king commands, if, preserving the order of civil peace, either he is certain that what is commanded him is not against the precept of God, or he is not certain whether it is." Therefore, although a subject is doubtful concerning the justice of a war, nevertheless he can licitly serve as a soldier at the command of his prince - and by what reason? relying on the reflex principle that the prince has a certain right, so that always, and so long as the injustice is not established, he be obeyed.²

2. From reason. Because he who acts thus prudently judges that in these circumstances he acts lawfully and honestly: since the judgment concerning the honesty of his act rests no longer on weak reasons of probability, but on a most firm supervening, that is, reflex principle. Cf. n. 44 and 57 ff.

39. As Beaudouin, O.P., excellently explains (de Consc., p. 42 ff.): When doubt stands in the principles, the intellect is determined by the will, which chooses to assent determinately to one part, on account of a motive which is sufficient for moving the will but not the intellect, as being that it seems good and fitting to assent to this part. Therefore from the end of virtue the will is rectified; by the reflex principle reason is certified.

As regards obtaining certitude, surely the reflex principle cannot do more than the direct principle, if the discussion is about the truth of the opinion; but it can, if the discussion is about its use. For the truth of an opinion must always be distinguished from its use, that is, the true from the lawful. For it is one thing to ask whether this opinion is objectively true; it is another to ask whether it is lawful to use this opinion in practice, as is clear in the cited example of the soldier (I, 21).

Nor from these things does the absurdity follow, namely that concerning the same object there can be doubt and certitude at the same time; for in this case the doubt and certitude are not concerning the same object. The doubt regards the truth of the opinion in itself, or objective morality; the certitude regards subjective morality, that is, the honesty of the action in him who uses such an opinion. Thus, for example, one doubting whether a contract is usurious indeed doubts concerning the truth of the opinion affirming it; but with this doubt there well consists certitude that the contract can be honestly entered into, which certitude is drawn from this reflex principle: "A doubtful law does not oblige" (cf. n. 46).

"Hence it appears that reflex principles do not solve the particular question, but leave it uncertain; only the practice is certain, because reflex principles fix a certain rule for directing practice in that doubt." Therefore with our Holy Doctor we conclude: "For acting licitly we must have moral certitude concerning the honesty of the action, either direct, if we use an opinion morally certain, or reflex, if the opinion is only probable" (I, 23, 64; cf. Diss. 1757, n. 34, 53, 54).

40. From the things said the following rules flow spontaneously for practice:

Rule 1. He who is practically doubtful is bound, as long as he remains in such a state, to follow the safer part according to the axiom: In doubt the safer thing is to be chosen (I, 77).

The safer part is said to be that which stands for the law; the less safe part, that which stands for liberty. Therefore he who embraces the safer part, namely by omitting a work doubtfully prohibited, or by doing one doubtfully commanded, certainly fulfills the law, and does not sin even materially. But he is bound to this by the very fact that he has and preserves a practically doubtful conscience, as is clear from what was said (principle I, n. 36).

Rule 2. He who in practical doubt does not wish to follow the safer part (or cannot, for example because he must intimate the law of God not to himself, but to others), should inquire into the truth with moral diligence, and then act according to the truth found. Prudence dictates this, and justice demands it, that to each his own be rendered. For in the present case law and liberty in some way litigate with each other. Whence reason, which in man is like a judge in a city, must, if possible, hear and weigh the arguments of each litigant, and then adjudicate the cause to him to whom right in reality favors (1.2, q. 104, a. 1).

Moreover this inquiry is to be made with moral diligence, that is, with diligence which truly corresponds to the gravity of the question, the weight of the reasons, the condition of the person, and the other circumstances of things. Thus, for example, for an uneducated man, who is incapable of forming conscience for himself, it will be enough to consult the pastor or confessor, or another pious and learned man; and then to act according to the counsel received. But for the theologian and confessor, to whom by office it belongs to impose just burdens on others, greater diligence, as is clear, must be applied (I, 24; V, 4; H. Ap., III, 33).

Rule 3. If the doubt, all things weighed, is noticed to be empty, it must be held as nothing. The reason is that morals are to be composed from a prudent judgment; but a doubt which, all things weighed, remains merely negative, and is nothing other than an empty fear or suspicion, is by no means opposed to a prudent judgment. Therefore it can be laid aside without another reflection; and thus either the liberty or the obligation which existed before the doubt perseveres, and in practice is held for truth (I, 11, 24, 37; VI, 908).

Rule 4. If the doubt is founded and, the matter diligently weighed, is recognized to be strict and invincible, a practically certain dictate must be formed according to reflex principles, as was said above (n. 38).

324. Notions. Certain conscience is that which, without prudent fear of erring, judges that some act is either licit or good or evil, and therefore here and now to be done or omitted. Since morally certain conscience is altogether required, so that it is never licit to act with a practically doubtful conscience, it is helpful to explain briefly what certitude is and how it is divided.

Certitude is customarily defined: the firm adherence of the mind to some truth without fear of erring; or, as St. Thomas⁶⁰ says: "Firmness of adhesion of the cognitive power to its knowable object." Therefore certitude is the effect of evidence (intrinsic or extrinsic). For when some truth appears evident to us, we assent with certitude; but as long as evidence has not been present, neither can certain assent be present. This evidence is sometimes intrinsic, namely if it arises from the very nature of the thing clearly perceived; for example, man has intrinsic evidence concerning the truth of the calculation 2 + 2 = 4. But sometimes this evidence is only extrinsic, namely if it is founded upon either human or divine testimony. Thus a boy is certain that this man is his father, because it has been narrated to him so by trustworthy persons; thus all Catholics are certain concerning the truths of faith, because God Himself revealed them. Truths certainly known from intrinsic evidence are evidently knowable; but truths knowable from extrinsic evidence are evidently credible. But even if certitude arises from the evidence of truth, nevertheless from this it is not licit to conclude that certain and true conscience coincide. For since the dictate of conscience is as it were the conclusion of some reasoning, and since error can slip into reasoning, it follows that conscience can be false or erroneous and nevertheless certain. Hence above in n. 307 we proved that an invincibly erroneous conscience sometimes exists, which indeed is certain, but objectively false. Hence it is said briefly: true conscience regards the truth of the object; but certain conscience regards the subject's firm adherence.

⁶⁰ 3, dist. 26, q. 2, a. 4.

325. Divisions. 1. Certitude is divided into metaphysical, physical, and moral. Metaphysical certitude is founded in the very essence and connection of ideas and excludes every possibility of falsity, and therefore is also called absolute certitude, because the contrary proposition is absolutely false and in itself so repugnant that not even God Himself could make it true. This certitude is conveyed, for example, by the first moral principles: good is to be done, God is to be worshiped, etc. - Physical certitude excludes falsity not indeed absolutely, but with the physical order standing thus. It is physically certain, for example, that I am going to die, that the sun is going to rise tomorrow, etc., because, unless a miracle is going to derogate from the physical order, it is certain that these effects are going to occur. - Moral certitude excludes every fear of erring, with attention to the moral order of things. Thus, for example, I am morally certain that the Pope is a worthy man, that my friend perfectly known to me does not tell a lie, etc.

2. Certitude is divided into strict or perfect and broad or imperfect. For according to the greater or lesser weight of reasons on which it rests, certitude, that is, firmness of adherence, admits diverse grades, which nevertheless can all be reduced to two. Strict or perfect certitude is that which altogether excludes every reasonable doubt, so that its opposite is supported by no prudent motive. Cf. the examples brought above in n. 1 for moral certitude. - But broad or imperfect certitude⁶¹ is that which rests indeed on a grave motive, but against which not only the possibility of error stands, but certain lighter reasons also fight. Thus, for example, it is morally certain that the three acts of the penitent are the proximate matter of the sacrament of penance, or that Christ immediately instituted all the sacraments, although some authors hold the contrary. Concerning this broad certitude St. Alphonsus⁶² writes: "To form the moral certitude of some opinion, it is not required that authors holding the opposite lack every reason even light; but it suffices if that opinion, all things having been weighed, appears so true that there scarcely remains to the contrary the appearance of truth, or that the contrary seems not sufficiently probable." From these words of the Holy Doctor it follows that, whenever he calls some opinion not sufficiently probable, he holds the opposite as morally certain and therefore to be followed.

3. Certitude is divided into speculative and practical. Speculative certitude is that which regards the truth of the thing viewed objectively, without direct relation to a practical case. Thus, speaking speculatively, touches are licit, kisses are not prohibited; but in a particular case this certitude sometimes fails; indeed it yields to contrary certitude. - Practical certitude regards the act to be posited here and now, as clothed with all circumstances, for example, the omission of the recitation of the Breviary is licit for me today because of my infirmity.

4. Certitude is divided into direct and indirect or reflex. Direct certitude is called that which arises from clear internal principles manifestly demonstrating the morality of the act to be posited. Thus, for example, a son says to himself: since due obedience is to be rendered to parents, I am bound here and now to obey my father legitimately commanding. Indirect certitude is not obtained by direct and internal principles, but by indirect principles extrinsic to the thing. For example, a subject doubts whether a matter commanded by a superior is licit or not. But since he is persuaded that the superior is wise and God-fearing, he has recourse to a reflex and most true principle: "In doubt the presumption stands for the superior"; and from this he concludes with moral certitude: therefore I can, indeed I also ought to obey the precept of the superior. Speech will return below in n. 332 concerning these reflex principles.

⁶¹ This certitude is called by St. Thomas "probable certitude, which reaches truth in most cases, although in fewer cases it falls short of truth" (S. theol. 2, 2, q. 70, a. 2). The word "probable" here is not taken as it is customarily taken by moderns; otherwise probable certitude would be a contradiction in terms. Modern authors also call this certitude moral and broadly so called (cf. Marc-Raus, Inst. mor. I, 31).

⁶² Dissertation a. 1755, n. 52.

326. Principle. a) Only certain conscience (whether directly or indirectly) is the right rule of morals; b) but for acting licitly, certitude broadly so called ordinarily suffices.

a) This principle is admitted by almost all theologians.⁶³ The reason is that man is bound to apply serious diligence so that he may conform his acts to just law, as was said above in n. 306. Now unless moral certitude of conformity with law is present, neither has man applied sufficient diligence, because it is not so difficult to obtain practical moral certitude in our actions. Then he who acts without moral certitude concerning the licitness of his act sins by exposing himself to the proximate danger of formally sinning and offending God. Moreover, it is not licit voluntarily to expose oneself to a proximate danger of sinning; for he who does that which he reasonably suspects to be sin virtually and interpretatively wills sin itself. - The same is established from St. Thomas,⁶⁴ who a) requires for conscience that it be brought into no doubt; b) calls conscience the application of science, that is, of certain knowledge, to an act.⁶⁵

b) Nevertheless certitude in every respect is not required, but broad certitude ordinarily suffices. For "certitude is not to be sought in the same way in all things, but in each matter according to its proper mode. But because the matter of prudence is contingent singulars, concerning which human operations are, the certitude of prudence cannot be so great that solicitude is altogether removed."⁶⁶ What St. Thomas here teaches concerning the certitude of prudence, the same holds concerning the certitude of conscience. That broad moral certitude truly suffices for acting licitly also appears manifestly from proposition (3) condemned by Alexander VIII: "It is not licit to follow an opinion even the most probable among the probable."⁶⁷ For even the most probable opinion is not absolutely certain, and therefore, if it is licit to follow the most probable opinion, likewise it is licit to follow an opinion morally and broadly certain, which lacks absolute certitude. Finally the reason is added: absolute certitude in human acts is often altogether impossible. But no one is bound to the impossible. Therefore absolute certitude is not required in human acts, but broad certitude suffices. - In a few cases broad certitude does not suffice, but strict certitude is required, namely when even a slight doubt renders the act illicit, as is accustomed to happen if there is question of the validity of the sacraments. Hence outside the case of grave necessity it is not licit to administer the sacraments with matter which is not certainly valid.

⁶³ Lacroix (De consc. l. 1, n. 47) cites as adversaries Camargo, Taberna, and certain others of small authority.

⁶⁴ Quodl. 8, a. 13.

⁶⁵ S. theol. 1, 2, q. 19, a. 5.

⁶⁶ Ibid. 2, 2, q. 47, a. 9 ad 2.

⁶⁷ Denz. n. 1293.

327. Scholion. On practical certitude alone as necessary. Since conscience is an act, as has already often been said, it suffices and is required for acting licitly that practical certitude be present, but not speculative certitude. For in moral theology there are very many controverted opinions in which speculative moral certitude is altogether lacking, for example, whether customs-duty laws are merely penal laws, whether painting is a servile work, etc. Certainly it is altogether impossible in these controversies to obtain speculative moral certitude, because the reasons given on both sides are grave and the Church has given no definitive decision. But acts to be posited not rarely occur from these controverted questions. Then therefore, while speculative doubt stands, practical certitude is to be sought, as will be said in the following article.

47. Definition. - A certain conscience is that by which someone firmly and without fear of erring judges that something is good or evil.

Now certainty, or the certain generically, is that which determines the mind to assent. Certainty is divided in many ways; there is certainty of the supernatural order and certainty of the natural order. This latter is subdivided into metaphysical, physical, and moral certainty.

That is metaphysically or mathematically certain which is so essentially disposed that in no other way and by no power can it be or be conceived. That is physically certain which, although it does not have it from its essence that it cannot be otherwise, and therefore absolutely could be otherwise, nevertheless according to ordinary power cannot be otherwise. These things having been premised:

Moral certainty generically (for there are several species of it, as we shall see below) is that which neither by its own nature (and thus it differs from metaphysical certainty), nor from the ordinary course (and thus it is distinguished from physical certainty), has it that it cannot be otherwise, but is so disposed according to the estimate of the inner sense. More briefly it can be defined: that which is ruled by the laws which men use in their acts, or also: that which rests upon the estimate of the inner sense.

Moral certainty in species. - There are four species of moral certainty: direct and indirect; perfect and imperfect.

Direct moral certainty is that which is sought from direct principles, or which is obtained by reasons sought from the very nature of the thing. Thus it is directly certain that children owe love to parents; for the certainty of this matter is sought from the very relation of cause which parents have toward children.

Indirect or reflex moral certainty is that which is obtained by a reflected act of the mind, or which is sought from reflex or concomitant and indirect principles. Therefore this is not borne immediately upon its own object as direct moral certainty is, but mediately, namely through principles adduced from elsewhere. Similarly it does not have the ultimate reason of assenting in the object itself, as direct certainty does, but in something else, upon which the mind or intellect reflects. Thus, when there is a probable opinion concerning the non-existence of a law and another equally probable concerning its existence, then the non-existence of the law is not directly certain, but doubtful. But (and this is the reflex principle) a doubtful law does not oblige. Therefore, when it is equally probable that the law does not exist as that it exists, then this law does not oblige. And since the aforesaid reflex principle is certain, the conclusion also is certain.

Perfect moral certainty, which is also called absolute and strict, is that which is so founded upon moral laws, that is, those by which men are governed in their acts, that it is clearly perceived that the proposition cannot be false, for example, parents are to be honored.

Imperfect, or broadly so-called, certainty is that which belongs to those propositions in which it is not absolutely repugnant that there be error, although this can happen very rarely. This alone is understood when Moralists call something morally certain, and it admits various grades; namely, it is called highest when against it possibility alone militates; ordinary, if, besides possibility, certain slight moments militate against it, which, all things weighed, are reasonably contemned.

Note. - Not even an opinion certainly more probable enjoys this imperfect certainty, if it is considered speculatively and in itself. Wherefore St. Alphonsus must be understood in a comparative and practical sense when he calls an opinion of this kind morally certain; for this reason also he calls it quasi morally certain. In the same way, an opinion solitarily probable, which is also called probable certainty, is practically held as in the place of morally certain. More broadly on these matters, nn. 52, 53, 68.

Principle I. - Conscience cannot be a legitimate rule of operating unless it is certain; namely, the practico-practical judgment or conclusion of the particular syllogism (n. 32, Cor. II) must be so firm that the agent in no way doubts concerning the formal licitness of his action, but without fear of erring judges that he, in acting thus, does not sin, or that this is licit for him here and now. The reason is 1° because everything which is not of faith is sin (n. 35, II); 2° because he sins who deliberately commits himself to the danger of sinning; but he commits himself to such danger who operates uncertain whether he acts rightly and honestly; therefore, one operating thus sins. And indeed he who, uncertain concerning the goodness of the action, nevertheless acts, implicitly and interpretatively says: I wish to do this whether it is licit or illicit; which is a virtual contempt of the law. Likewise, he who, uncertain whether this or that is mortal, nevertheless operates, is so disposed in soul that he as it were says: even if to do this is a mortal sin, nevertheless I shall do it; which certainly is a grave delict. - Wherefore he who acts probably does not for that reason act prudently.¹

II. For the formal honesty of an action, imperfect moral certainty, even ordinary certainty, suffices, nor is the highest required.² This is the most common doctrine. - It is proved: 1° Because imperfect certainty, although only ordinary, is true certainty with respect to things to be done; and therefore one operating from such a conscience truly operates from faith; for from such certainty prudent men act, even in matters of grave moment. 2° Because perfect certainty, or even the highest imperfect certainty, generally cannot be had in particular moral actions; therefore, since God does not command impossibilities, imperfect certainty suffices.

III. For formal honesty, indirect certainty suffices, as will be proved below.

IV. It suffices that someone be certain, in act, concerning the licitness of his action; namely, it is not necessary that he judge reflexively that he is certain; it is enough that the operation be done as indubitably licit, or that no danger of formal sin appear. This is plain in itself.

St. Thomas, IV Sent., d. 21, q. 2, a. 3; Quodlibet VIII, q. 16, a. 13.

213. Notions. - Conscience must also be certain. Now by reason of the subject, that is, on the part of the act, assent, or adherence to the object, conscience is either certain if its judgment adheres firmly to something, or uncertain if it does not adhere firmly; and the latter is doubtful if it does not adhere but judgment is suspended, or opinionative if it adheres but with fear of the opposite. Certain conscience, therefore, is that which formally in itself and in all the principles from which it is formed excludes fear of the opposite, and therefore firmly and without fear of erring judges that something in particular is licit or illicit.

Now we ask whether conscience, in order that it be the rule of acting, must be certain.

214. Principle. The only legitimate rule of acting is certain conscience, by which, namely, man prudently forms for himself a certain judgment that the action to be placed here and now is placed licitly and honorably; hence such conscience is required for operating licitly.

It is proved: 1) from the Scriptures, Rom. XIV, 23: Everything that is not from faith is sin; but he who is uncertain does not act from conviction, and therefore what is done from uncertain conscience is not from faith or persuasion; therefore it is sin. The Apostle explicitly states this conclusion, inferring it from the said principle: He who distinguishes (that is, who hesitates or doubts whether it is licit to eat some food), if he eats, is condemned, because not from faith. Hence Eccli. XXXVII, 20: Before all works let a true word go before you, and before every act stable counsel.

2. By reason: a) he who acts with uncertain conscience has a reasonable and founded fear concerning the malice, and uncertainty concerning the goodness, of his act. But he who is uncertain concerning the goodness of his act and nevertheless acts, wills to place it whether it be against the law or not, and thus hypothetically consents to evil, and has an evil will, and contemns the law of God and acts badly. This is confirmed by the example of a servant who, doubting whether something is against the will of his master, would neglect to inquire into the will of his master if he could and nevertheless would act: he would be judged guilty by all. Likewise, one who would do that which he suspects offends a friend would be judged by this very fact to offend him and contemn his friendship.

b) He who voluntarily exposes himself to the proximate danger of sinning formally and offending God acts badly. But he who says, "It is uncertain whether this is really evil," and acts, operates rashly because he does what he fears offends God, and thus exposes himself to the proximate danger of sinning formally and offending God. Therefore he acts badly. Hence Augustine against the Donatists: "To receive (Baptism) in the party of Donatus... if it is uncertain whether it is a sin, who would doubt that it is a certain sin?"

1. Book De Baptismo contra Donatistas, c. 5. - Several theologians call the value of this argument into doubt. Nevertheless, to one considering it well, it will appear that it does not substantially differ from the preceding argument; but the special mode of proposing it is already found in St. Thomas (Quodlibet VIII, a. 13), in the case proposed in which someone "is led into a certain doubt from contrariety of opinions..., if, while such doubt remains, he has several benefices, he commits himself to danger, and thus without doubt sins, as loving a temporal benefice more than his own salvation." In the same way in IV Sent. d. 21, q. 2, a. 3: "He who commits or omits something in which he doubts there is mortal sin, commits himself to danger." Likewise in Scotus, q. 2, prologue, and in IV Sent. d. 30, q. 1; and in St. Alphonsus, Theologia Moralis, l. 1, n. 22.

c) Conscience is the rule and measure of our acts. But a measure cannot be ambiguous, but must be certain. Therefore conscience must be certain.

215. Applications. - From the foregoing it follows:

1. That one who does not have a certain practical judgment concerning the liceity of an action, or certain conscience, cannot act; and if he must act altogether, he is bound to do what is safer, namely, what favors the law (or obligation) more and removes him more from the danger of acting badly. Hence the axiom: In practical doubts the safer way is to be chosen.

2. That one who does not have a direct, speculative-practical, certain judgment concerning the objective and material honesty of the action does not for that reason always lack a certain practical judgment concerning its subjective and formal honesty, but sometimes has a certain conscience from a certain higher principle and from a reflex judgment of the intellect reflecting upon its own act and applying that principle; for example, although the morality of such an action is doubtful to me, it is certain to me that I must place it if a superior commands it, both because presumption stands for the superior, who therefore is not to be deprived, on account of the doubt of subjects, of his right of commanding, which he certainly holds, and because the right order of the common good forbids subjects to deny obedience unless it certainly appears that the superior abuses his power; although I doubt whether such a work is servile, it is certain that I can exercise it if the pastor has said so; although in itself it is uncertain whether a sacrament is validly and licitly ministered in such matter, it is certain to me that regularly, out of reverence toward the sacrament, I must abstain from such ministration, and in a case of necessity employ it; although such a man is probably guilty, it is certain that he cannot be condemned by a judge unless he is proved guilty with certainty, etc., for there are many similar cases as is determined in the special treatises.

3. Especially, that a practical judgment is held as certain, even while speculative doubt remains, and a certain conscience of special obligation arises whenever there is present a certain and absolute obligation of obtaining a determined end which otherwise perhaps would not be obtained; in other words, whenever a good effect (for example, salvation, a sacrament, health) must be absolutely obtained, or an evil effect (damnation, death, harm) must be absolutely avoided, and there is doubt not only about the honesty but also about the necessity or efficacy of the means required for this and about the validity of the act or fact. Then, namely, a certain higher law intervenes, which dictates that in doubts concerning the validity of an act to be placed, the safer thing must be done. From this reflex judgment an objectively uncertain obligation becomes subjectively certain. The reason is that, if the honesty of an action depends upon our reason and conscience, the value of the action or the averting of harm does not in the same way; for our doubt or judgment is not able to change the nature of things, nor therefore to render a null act valid, or to bring it about that the due effect arises from the action, or to impede harm from following from it; for example, a doubt or an opinion, however probable, cannot bring it about that what is not a sacrament be a sacrament, or that what is rather poison be medicine. Hence in the case a certain natural law prohibits exposing oneself to the danger of not obtaining the end or of bringing in evil, namely, by employing a means which perhaps is ineffective or harmful. To expose oneself to a danger of this sort, in species, is especially illicit in doubts concerning things necessary by necessity of means to eternal salvation: namely, in these things one must especially act more safely and more certainly.

1. Let it be noted that one thing is necessary by necessity of means, another by necessity of precept alone: the latter is only necessary for the end because it has been prescribed, for example, hearing Mass; the former is necessary because it is a means without which the end cannot be obtained, for example, Baptism or contrition for sins.

4. That one who is uncertain, not indeed concerning the value of the act or the necessity of the means, but concerning only its honesty or only the necessity of a precept, must, before he can act, lay aside the doubt either by inquiring into the truth more diligently or by consulting the more learned, and form for himself a certain conscience concerning the honesty of the action, at least indirectly from a reflex judgment applying some general certain principle. Prudence teaches how this can be done in various cases and doubts, all the circumstances being considered, and therefore it will be explained in the treatise on prudence. But if such means here and now are lacking, he must abstain from the action; or if he absolutely cannot suspend it, he must choose what is safer, as was already said above in 1).

S. Th. II-II, q. 1, a. 4; q. 2, a. 1; q. 4, a. 8; Q. D. de Ver. 14, a. 1.

71. Various states of mind: doubt, suspicion, opinion, certitude. - Besides certitude, which is the state of a mind firmly adhering to one part totally and determinately, a threefold state of mind can be distinguished, with respect to adhesion or assent to the object: doubting or suspension of assent, - suspicion or inclination to assent, - opinion or assent, but not firm assent, because it is with fear of the opposite.

1. Doubt properly so called, or positive doubt, is the state of an intellect placed in equilibrium, which, namely, suspends assent and adheres to neither part, nor inclines more to one part than to the other, but wavers between the two on account of the apparent equality of reasons. It differs strictly from nescience, which is suspension of assent on account of a defect of reasons moving to assent, and which is improperly called doubt and is customarily called negative doubt.

2. Suspicion is the state of a mind inclining more to one part than to the other, without assenting to it, because for it there stands a reason, or an excess of reasons, a little greater than for the other.

3. Opinion is the adhesion of the intellect to one part without being totally determined to it, or the acceptance of one part with fear of the other, because there are sufficiently graver reasons for one part than for the other.¹

¹ Cf. II-II, q. 2, a. 2.

Since in human operable matters a little is reckoned as nothing,² because it helps or impedes little for obtaining the end, and therefore it does not much matter whether it is done thus or thus, for that reason slight reasons are reckoned as none, and a slight excess of reasons as none. Whence although psychologically they differ, nevertheless morally suspicion is judged doubt; positive doubt on account of slight reasons is judged negative; only doubt on account of grave reasons equal or almost equal on both sides is judged positive;³ opinion founded on graver reasons in such a way that against it there stand only slight reasons is judged practical certitude, to which it comes near and from which it is separated by a slight distance. Hence in practice there remain only doubt, opinion, and certitude.⁴

² "Reason takes what is slight as almost nothing," I-II, q. 14, a. 4. Cf. St. Alph., Th. M., book I, n. 55.

³ St. Alphonsus, Th. M., book I, n. 20; and the Dissertation of the year 1762.

⁴ Cf. Q. D. de Ver. 14, a. 1.

72. What probable opinion is. - Opinion is properly taken subjectively, and is a judgment by which we adhere to something as true, not firmly, but with fear of the opposite, because for it alone there stand grave reasons, or reasons sufficiently graver than for the opposite;⁵ whence although the truth is not manifested, nevertheless there is had a notable appearance of truth. Often, however, it is taken improperly, objectively, for the doctrine to which we adhere in this way; but this is not opinion, but that which we opine and approve by judgment, and therefore it is properly called probable or truthlike; hence such a doctrine is often called a probable opinion.⁶

⁵ We speak thus because of the manner of speaking of the equiprobabilists, who acknowledge only reasons a little graver and notably graver. They affirm with us that these latter found certitude broadly so called; but that reasons a little graver do not suffice for founding opinion, or the assent of one part with fear of the other, is manifest; whence in practice they do not distinguish opinion from certitude broadly so called. - But according to others, reasons can be so notably graver than the opposites that the intellect can adhere to them, although with fear of the opposite; yet not so notably that they constitute prudential certitude. Therefore, lest confusion arise, we abstain in the definition from the word "notably," and we say that opinion is founded on reasons which are sufficiently much graver than the opposites, so that the excess is not slight but grave, without however being altogether grave.

⁶ Thus passim in St. Alphonsus and recent authors.

Now probable is that which is worthy to be approved, which is apt to move a prudent man to assent and merits the assent of a prudent man; whence properly it is that for which there stand reasons absolutely grave and relatively graver than for the opposite, and therefore it is more often joined with truth than with falsity; otherwise it would not merit approbation, nor would it be worthy to be approved rather than the opposite, nor would it be like the true.⁷ Therefore only the doctrine more founded is probable in the strict philosophical sense; whence Aristotle (Top. I, c. 1): "Probable things are those which seem so to all, or to most, or to the wiser, and among these either to all, or to most, or to the most known."

⁷ This definition is rejected almost unanimously by the more recent Probabilists, indeed it is held to be something unheard of in Philosophy; according to them, probable properly is everything for which there stand grave reasons, even less grave ones. Yet our definition is generally admitted by philosophers of the Dominican school, "in which," as St. Alphonsus says, Th. M., book I, n. 80, "great doctrine has always flourished," indeed even by certain authors of the Society of Jesus, and it was commonly handed down by the philosophers of the middle age. That doctrine, says de Caigny, On the Genuine Moral System of St. Alphonsus, n. 263, "seems in no way to differ from the ancient definition of probable which the Angelic Doctor and other scholastics commonly handed down until the sixteenth century: which doctrine, like very many others, was rejected in the time of the false reformation; but in our days, like so many others, deserves to flourish anew in the Schools."

73. Opinion is an adhesion of the intellect commanded by the will. - Since the intellect does not have evidence of the thing, it does not adhere to it from the necessity of its nature, by which it would be carried to it without impediment, but adheres only dependently upon the free will, which moves it to assent (II-II, q. 1, a. 4). Namely, one thing is the judgment by which we affirm that on one side there are graver reasons and on the other side reasons are not present or are less grave: this judgment is necessary, because the intellect, sedulously comparing the reasons, cannot but see which are the graver; another thing is the judgment by which we adhere to the more founded part, and approve it and make it our own: this judgment is free from the motion of the will and is the judgment of opinion, while the former is presupposed so that the will may be able rationally to incline the intellect to adhere to that part.

Hence the will 1) can refrain from commanding assent, and thus will be the cause that the intellect suspends assent;

2. although it cannot directly compel the intellect to judge that there are grave or graver reasons, and yet to adhere to the less grave, nevertheless indirectly it can turn the intellect away from consideration of the graver reasons and bend it to consider the less grave reasons, which are also worthy of a certain attention and consideration.⁸ Indeed,

⁸ The reason why the will cannot directly determine the intellect to adhere to the less founded part is that the intellect is not, like the will, a free power, but a necessary power, not something blind, but a spiritual light; whence it necessarily sees the greater likelihood and tends toward it. Even Fr. Arendt was compelled to concede this in his Critique of the Apologetic Work of Fr. de Caigny, p. 23: "Therefore, in order that the will may obtain the assent which it wishes, it will be necessary for it somehow finally to avert the attention of the mind from contrary motives, and to see that the memory of the probability previously judged in those motives is erased, and at the same time that weights from elsewhere are increased for the part which the will itself favors." In this indirect way, namely, by causing the opposite reasons, in the course of time, to vanish totally from the mind through forgetfulness, the will can move the intellect to adhere to less grave reasons. - But what he adds on p. 40, that the will, on account of an extrinsic reason, for example the authority of another, can command the acceptance of one part which of itself is equally probable as the other, can be admitted if that authority increases the probability of one part; or it must be understood in this sense, that that authority is a sufficient motive for judging that following that part is good in practice; not however that it is a sufficient motive for judging that part to be theoretically more truthlike. For the intellect necessarily sees each part to be founded upon equal reasons, and consequently necessarily judges that neither is to be adhered to as true or more founded, and it tends toward neither. "When," says St. Alphonsus, Th. M., book I, n. 71, "there is present on the other side an equally probable opinion, then on neither side can there remain any probability, or probable reason apt to draw to itself the prudent assent of a man; for from these equal properties nothing other than mere doubt results... St. Thomas clearly teaches this, De Ver., q. 14, a. 1... When two probable opinions occur, they suspend judgment just as if no probability existed on either side." And n. 78: "Where two opinions concur equally probable, neither remains probable, but only doubtful."

3. it can apply the intellect now to one part, now to the other, so that it wavers between the two. In these three cases the will does not act conformably to the nature of reason, nor therefore rightly;⁹ yet because it can do this, therefore

⁹ "As often as it certainly appears to the intellect that truth stands much more for the law than for liberty, then the will cannot prudently and without fault adhere to the less safe part: since in that case a man would act not resting upon his own judgment, but rather through a certain effort which he would impose by his will upon the intellect, so that it might be removed from the part which appears to him much more truthlike," St. Alphonsus, Th. M., book I, n. 56. And n. 69: "Another principle of certain probabilists is this, that when each opinion is probable, a man suspends judgment concerning the safer opinion, and, leaning upon the probability of the benign opinion, acts. But Fr. Berti justly also rejects such a principle; for it by no means can render us certain concerning the honesty of the action, since this suspension of judgment is merely voluntary; whence it cannot excuse from ignorance being truly vincible, and therefore in this way doubt certainly cannot be put aside." - And Arendt himself admits this, o. c., p. 22: "The will indeed will rightly and without any fault move the intellect to give assent to the thing itself, if it has not commanded an assent firmer than the motives are able to require; but culpably if it has induced the intellect to assent to the thing itself either more firmly than the motives bear, or without any fear, and hence as if the thing were objectively evident."

a) opinion is sometimes called doubt broadly so called;¹⁰

¹⁰ Cf. St. Alphonsus, Th. M., book I, n. 67.

b) the dwelling of the intellect in considering less grave reasons is by some improperly called opinion; whence

c) moralists are accustomed to speak of opinion as more, equally, and less probable.¹¹ For for them probable is taken in a broad sense and is everything which, if not worthy of proof, is nevertheless worthy of attention and consideration, namely, that for which there stand grave reasons, even reasons less grave than for the opposite.

¹¹ The manner of speaking can also be explained in an objective sense concerning an opinion which exists among different persons, so that the opinion of certain theologians seems more probable to someone and therefore is his opinion, and the opinion of others appears to him equally or less probable than the other, and is not his opinion. The old writers are to be understood thus.

74. Various degrees of probability. - By reason of the gravity of the foundation or of the firmness of the motive, the probable has several degrees, so that it has so much more of probability as it has of gravity. And indeed:

a) If it is considered absolutely in itself, from its approach to the truth, three degrees are distinguished: truly and solidly probable - very probable - most probable, according as the reasons are grave - or very grave - or so grave that scarcely any prudent fear of the opposite remains.

Below true probability from a truly grave motive, there can be an imperfect appearance of truth from a doubtfully grave motive or from slight motives which do not merit the assent of a prudent man: this they improperly call doubtful, or light or slender, probability.

b) Comparatively to the opposite, however, there are distinguished: uniquely probable and not probable - probable and equally probable - more probable and less probable - indeed also much, very, notably more probable, and much less probable.

But in order that the reasons upon which probability is founded may be rightly estimated, it is necessary that they be considered both absolutely, so that according to themselves they are grave, and relatively, i.e., with attention to the reasons in the opposite direction:¹² for it can happen that a reason grave in itself, comparatively to another, is judged slight, for example if the contrary is very notably more probable,¹³ or even none, if the contrary is certain.¹⁴

¹² Concerning those who would not weigh opposite reasons, Lehmkuhl writes, Th. M., book I, n. 190: "He who is accustomed so rashly (namely, by not weighing the reasons of the contrary opinion) to pour forth his opinions... does not deserve the name of theologian."

¹³ Then the first sentence can only be slenderly and doubtfully probable.

¹⁴ For example, from a decree of the Church. Then from the motives there arises a difficulty perhaps here and now insoluble, but not probability.

Yet it does not seem to be denied that, even in moral matter, there can be opposite reasons and sentences which are truly grave and solidly probable, not only because they appear equal to each other and equally probable, but even when one seems more founded or more probable, the other less founded and less probable, without however the former being judged much, very, or notably more probable. And then the intellect, in adhering to the more probable sentence, can and must at the same time judge that the other, to which it does not adhere, is founded and in some way, though less so, probable.

By reason of security, the probable is safe, safer, or less safe, according as it wholly removes, or more, or less removes, the danger of sinning, either formally or even materially.

And so safer and more probable do not sound the same. Probability is said from the appearance of truth, security from the removal of danger, in this case of sin; whence the more probable is that which has a greater appearance of truth than the opposite, the safer that which more removes the danger of sinning even materially, or of transgressing the law. Therefore, since that which favors the law removes the danger of sinning more than that which favors liberty, for that reason that part which favors the law is safer and that which favors liberty is less safe. Hence the safer can be less probable, for example, if it is less probable that an obligation exists; - and on the contrary the more probable can be less safe, if it is more probable that the obligation does not exist. Thus, for example, the opinion of St. Bonaventure, establishing that after sin confession must be made at once, is safer; the opinion of St. Thomas denying this is more probable.

75. Various species of certitude. - Certitude A. is one kind when it is strictly so called, fixed, demonstrative, and philosophical or speculative, which excludes every fear of erring, and therefore is the determination of the intellect to one thing.¹⁵ This, on the part of the negative element, i.e., insofar as it excludes every doubting or fear, does not admit degrees but is in the indivisible; - on the part of the positive element, i.e., insofar as it adheres firmly to the object, it is greater or lesser. And indeed on the part of the cause, i.e., by reason of the firmer motive and of that to which error is more or less repugnant, natural certitude¹⁶ is metaphysical, physical, and moral, according as it is founded in the essential necessity of things (for example, the principle of causality, God exists), in their natural necessity (for example, from hydrogen and oxygen water is produced), or in the testimony of others which in the case is certainly demonstrated not to err (for example, the Chinese empire exists). But on the part of the subject, i.e., by reason of the manifestation of the object or of clarity, it is evident or intrinsic, which necessitates the intellect, and inevident or extrinsic, which does not necessitate and is taken from the authority of others.

¹⁵ "The firmness of adhesion of the cognitive power to its cognoscible." St. Thomas, II Sent., d. 26, q. 2, a. 4.

¹⁶ We are speaking only of natural certitude, and we abstract from the supernatural certitude of faith, which exceeds even metaphysical certitude. I, n. 721.

B. Another kind is broadly and improperly so called, conjectural or probable, which does not exclude every fear, but only the reasonable and prudent fear of erring. This is not strict certitude, because it does not prevent every fear, but is the greatest probability; and therefore even on the part of the negative element it admits degrees and is greater or lesser, more or less perfect, according as it excludes doubting more or less. By most it is called moral; for it suffices in moral matters, and moreover, although not physically, nevertheless morally it determines the intellect to one thing, insofar as there is lacking every serious reason for doubting which moves to the opposite. Whence although in practice it is equivalent to certitude, because it suffices for acting rightly and prudently, nevertheless it renders us morally, i.e., almost and equivalently, certain, rather than being true moral certitude. And therefore, that it may be distinguished from moral certitude strictly so called or historical certitude, it is better called practical and directive, because it suffices for acting and directing our acts; or prudential, because it suffices that men act prudently.

Certain conscience is that by which someone firmly and without fear of erring judges something to be good or bad.

Although certainty is distinguished in three ways among philosophers, that which is called moral is chiefly considered by moralists. This certainty, which rests upon the laws by which men are ruled in their acts, is subdivided into perfect and imperfect. The former is that which is so founded upon moral laws that the proposition is clearly perceived to be unable to be false. This is reduced indirectly to metaphysical certainty. The latter is that which belongs to those propositions in which it is not absolutely repugnant that there be error, although this can happen most rarely. This admits various degrees.

Doubtful conscience is that which remains suspended concerning the honesty of an action; for doubt is the suspension of assent between opposites.

Multiple doubt is distinguished, namely: 1st, positive or negative; the first is had when the intellect suspends assent on account of grave reasons for doubting, or at least reasons apparently such; but the other when assent is suspended on account of a defect of motives; 2nd, of law or of fact, according as it is concerned with the existence of a law, or its obligation, or with some particular fact; 3rd, speculative or practical, according as it is concerned with the abstract cognition of truth and in common, or with truth which here and now is ordered to work.

Only certain conscience is the right rule of morals, and therefore it is never licit to operate with a practically doubtful conscience. The reason is both because, according to the Apostle, Rom. xiv, 23: "all that is not from faith is sin"; and because the agent with a conscience not certain voluntarily admits the danger of transgressing a precept, and therefore, by virtually consenting to its violation, formally sins. But morally certain conscience, even imperfect, suffices; because only that certainty is required which alone for the most part can be had; otherwise the rule of acting, to which man is proximately subject, would be very little accommodated to the human condition. Cf. Baller., note (a), p. 41.

You Will Resolve. 1st. As often as someone doubts whether the act which he is about to place here and now is licit or not, he is bound to apply diligence congruent to the gravity of the matter and the condition of person and place for the inquiry of truth; let him consult upright and skilled men, investigate their practice, and weigh the reasons with the sole zeal for truth; otherwise he exposes himself to the danger of violating the law from negligence in inquiry, and by that very fact sins.

2nd. If he cannot inquire, nor by himself is able to weigh the reasons of each side, nor in another way, for example through reflex principles, free himself from doubt, let him embrace the safer part; because otherwise he would act in practical doubt, that is, with a conscience truly doubtful and without any certain judgment concerning the honesty of the action.

3rd. He who, after diligent and sufficient inquiry has been completed, still doubts whether there is a law commanding or prohibiting, is not bound to obey this law, if nevertheless he can form for himself a conscience from a reflex principle, namely that a law which cannot be found cannot oblige, as will be said below, where probabilism is treated.

4th. Merely negative doubt is to be held as nothing, because it is founded upon no reason at all, or upon a very light one. Therefore, even if it remains, because it cannot bring it about that the opposite moral certainty is overthrown, nevertheless the obligation presses, or liberty stands, according as it existed before. But if a prudent suspicion of error, resting upon a grave motive, arises for you, the doubt ceases to be merely negative, and you are bound to inquire. And so, when hereafter cases of negative doubt occur, you will easily dissolve them, this rule having once been established, and therefore we shall attend only to positive doubt. Cf. St. Alphonsus, n. 24.

Question 1. Does he who operates with practical doubt concerning the gravity of sin sin gravely?

Response. Affirmatively. For he who acts with a practically doubtful conscience, according to the common principles, sins in that species of sin, both moral and theological, concerning which practically, while he acts, he doubts. The reason is that he surely violates the grave obligation of taking care lest through voluntary ignorance or inadvertence he fall into transgressions of the law which could be grave.

Question 2. What is to be done in the case of a perplexed conscience, namely when someone, placed between two precepts, remains doubtful which of the two he ought to follow?

Response. 1st. Consult, if you can, a confessor or other prudent men, because in that case ignorance is vincible. 2nd. If you cannot consult and there is a necessity of acting, because the action cannot be suspended without grave harm, choose what seems to you the lesser evil, yet not so that you do evil, but so that you recede more from evil. Know, moreover, that the law of an inferior order ought to yield to the law of a superior order. 3rd. If each precept seems to you equally grave, choose anything, and you will not sin; for there is not given a necessity of sinning. Cf. St. Alphonsus, n. 10.

I. All theologians teach that penitents laboring under vincible ignorance must be instructed. The dispute concerns invincible ignorance alone. The precept of fraternal correction must be distinguished from the precept of giving instruction to the penitent, who is to receive the Sacrament of penance. The former, when hope of profit is wanting, does not press; but the latter binds even when the hope of amendment has been removed, on account of the reverence due to the Sacrament. All likewise teach that those penitents must be enlightened who labor under ignorance of the Trinity, of the Incarnation, of the Eucharist, and of the supernatural sorrow necessary for sacramental confession.

II. Sanchez, Lugo, Tamburini, the Salmanticenses, and Sporer defend the position that Confessors are not bound — nay, that they ought not — to enlighten penitents laboring under invincible ignorance of the mysteries which are not necessary with the necessity of means, and of the other truths of law, whether positive or natural.

III. This opinion seems to me false. All Christians are bound by a most grave precept to learn the truths necessary for the forming of our morals. Therefore Confessors ought to manifest truths of this kind to penitents who are ignorant of them. By what reason, I ask, can Confessors dissemble the manifestation of these truths? Perhaps because they foresee that their penitents are unprepared to receive it? Then those penitents are violators of the precept of learning and finding the truth, and are therefore unprepared to receive the Sacrament. I set the matter forth perspicuously. Just as the Confessor in the tribunal sustains the person of a judge, to absolve or to bind; of a physician, to heal wounds; of a doctor, to enlighten, instruct, and teach: so penitents approach this tribunal as guilty men to be absolved, as sick men to be healed, as ignorant men to be enlightened, instructed, and corrected. If the Confessor foresees that they are so unteachable and so given over to depraved desires that he hopes for no profit from the manifestation of the truth, by what reason can he presume them disposed and prepared for the Sacrament? He foresees them unteachable, rebels against the light, and obstinate in their ignorance — and at the same time he will judge these same men worthy to receive the Sacrament of penance?

IV. The Adversaries are pressed more closely. They all teach that the truth must be laid open when penitents labor under a vincibly erroneous conscience. But when penitents are foreseen to be unprepared, and rebels against receiving the manifestation of the truth, forthwith their ignorance, which until then was invincible, becomes vincible and crass. Therefore, even according to their own principles, the Confessor sins gravely if he does not manifest the truth; and the penitents receiving the Sacrament are sacrilegious. I prove the minor. Ignorance is vincible, according to all, when a way lies open to Christians of learning the truth of which they are ignorant; in our case this way lies open; therefore, if Christians refuse to learn this truth from the Confessor, their ignorance becomes vincible and crass. All this is most luminous.¹

¹ See Tome 2 of the Apparatus, Dissertation I, chapter 4.

V. The writers cited teach that penitents are not to be admonished by their Confessors who in good faith possess the goods of others, who enter upon usurious contracts, who practice pollutions in good faith, whenever it is foreseen that the manifestation of the truth will harm, and not profit, the penitent. Nay, some add — among them Tamburini — that the truth is not to be manifested even if the penitents would make right use of the knowledge, when the remedy is most difficult and infamy or scandal is feared. If a dying man, they say, is ignorant that he has heaped up a great sum of money by usuries and unjust contracts, and it is foreseen that, if admonished by the Confessor, he will not make restitution, then he is to be left in his ignorance. Tamburini says that this doctrine is especially necessary, above all to the Confessors of Princes and of Merchants; but it must be spat out as false.

VI. They object, first: when the manifestation of the truth is foreseen to be harmful and not profitable, no just end of revealing the truth presents itself; nay, say the Salmanticenses, treatise 20, chapter 5, point 3, number 27, in that case Confessors administer poison, while they seem to apply medicine. Answer. Christ the Lord foresaw that few would receive his law, and that very many would be rebels against it: did he for that reason abstain from promulgating it? Is there no just end of revealing the truth? Is it not a just end to guard the Sacraments, lest they be profaned by the unworthy and the blinded, who refuse to open their eyes to the light that freely offers itself?

VII. They object, secondly, the authority of St. Augustine, found in the chapter Si quis, On penance, distinction 7, saying: If I knew that it would not profit thee, I would not admonish thee, I would not terrify thee. Answer. St. Augustine speaks of fraternal correction, say some. But the holy Doctor there discourses of a dying man, to whom he urges penance; and he adds that he does not know whether it will profit him. For if he knew it would not profit, he would not urge it. Ignorantly, therefore, is this authority brought against us.²

² See Tome 2 of the Apparatus, Dissertation 1, chapter 4.

VIII. They oppose, thirdly: Innocent III, in the chapter Quia circa, On consanguinity and affinity, says: Thou mayest dissemble, that he may remain in the union thus contracted, since from a separation, as thou assertest, grave scandal may threaten. Answer. Some say that the Pontiff speaks of a Bishop or a Parish priest, not of a Confessor. Leaving this response aside, the true one is presented. The entire text of the Pontiff in the place cited is this: Further, concerning the man N., for whose dispensation — that is, the indulgence of remaining with her who touches him in the fifth degree of consanguinity — to be obtained from the apostolic See, a false cause was alleged to us, namely offspring; whereas before the dispensation was obtained, the only daughter whom he had had entered the way of all flesh, as thy consultation stated: thou mayest dissemble, that he may remain in the union thus contracted, since from a separation (as thou assertest) thou seest grave scandal to threaten. It is evident that the Pontiff approves the dispensation — which otherwise, on account of the falsely stated cause, was null — in order to guard against the scandal which he foresaw would arise from the separation of the spouses. See what the Gloss teaches in the same place.³ Ineptly does Navarrus cavil at this dispensation, as has been demonstrated in the place cited by the most luminous reasons. Wherefore the Casuists named wrongly oppose to us the testimonies both of Augustine and of Innocent.

³ See Tome 2 of the Apparatus, Dissertation 1, chapter 4, number 28 and following.

IX. I sum the matter up in few words. Confessors, that they may be able to absolve their penitents, must of necessity form this judgment: namely, that they approach that tribunal with a sincere heart and a contrite soul; that they sincerely will to observe all the commandments of the Law; that they are prepared to receive instruction in all the truths which the divine law commands to be known and kept. With these dispositions Confessors must presume their penitents to be adorned. Therefore they can in no way presume them adverse and rebellious to receiving the knowledge of the divine Law and of the precepts of which they labor in ignorance. But if they presume them such, it necessarily follows that they must also judge them most unworthy of the reception of the Sacraments. See more in the place cited.

X. Bertha married in good faith. Her marriage, on account of a hidden impediment, is null. If she be admonished of the impediment, she is placed in a proximate occasion of fornicating. If she refuse to render the debt, either she is killed by her husband, or mutual enmities and infamies arise between the families.

XI. Not a few devise cases occurring either never, or most rarely, that they may extort some decision, which they afterwards apply to cases happening everywhere. The Confessor sitting before the tribunal, before he absolves Bertha, ought to admonish her. She will be placed, you say, in a proximate occasion of fornicating, because she cannot be separated without scandal. This occasion will be a necessary one, not a free one; and by opportune remedies continence can be observed, until a dispensation be obtained.⁴

⁴ See Tome 2 of the Apparatus, Dissertation 1, chapter 4, number 48.

I. The Probabilists commonly all defend the contrary. La-Croix, book 1, question 5, number 14 and following, deceived by the authority of Terillus, cites St. Thomas for this opinion; but this is a most manifest falsehood. For St. Thomas most powerfully overthrows this opinion, as is evident from his following doctrine. Behold his doctrine, I-II, question 19, article 6: Good, he says, is caused by an integral cause, but evil by single defects. And therefore, for that to be called evil toward which the will is borne, it suffices either that it be evil according to its nature, or that it be apprehended as evil. But for it to be good, it is required that it be good in both ways. What could be more luminous? And what of that which is carried about in the common proverb: Good comes from an integral cause; evil from any defect whatsoever.

II. The doctrine of the Angelic Doctor is illustrated. The will cannot be right unless it be conformed to the eternal Law of God, which is the fountain of all goodness. This is the first rule, the first exemplar, of every created will that is good and right. But a created will directed by a reason erring invincibly, which proposes lying, theft, perjury, and other crimes as good, cannot be traced back to the divine will and to His eternal Law — unless we wish to pour the crimes back upon God.

III. Fr. Claude La-Croix answers, book 1, number 24: The will of lying is not traced back to God, nor is it approved by God per se — I concede; per accidens — I deny. Have you heard? Lying, then, is approved by God per accidens. God confers a reward per accidens upon liars. That you may perceive more clearly the horror of this doctrine, recall to mind the doctrine of invincible ignorance of the natural law, which the Probabilists defend — who consequently maintain, with better right, invincible ignorance of the positive law, divine and human, and of the true Religion. This being posited as certain fact, the wills of Infidelity, of Heathenism, of Mahometanism, the wills of the followers of Arianism, of Nestorianism, of Lutheranism, of Calvinism — these wills, I say, of so many peoples, directed by invincible ignorance, are approved by God per accidens. What more? Atheism itself must be traced back to God. For God himself, according to Molina, Arriaga, and Platel, the champions of philosophical sin, can be invincibly unknown. According to these authors there can be given an invincibly erroneous conscience which reputes fornication, pollution, lying, and similar crimes to be licit. Therefore these horrendous crimes will be crowned with an eternal reward.

IV. All this is confirmed. No action is meritorious of eternal life without the benefit of divine grace. If fornication, if softness, if lying, if other similar crimes, reputed honorable through invincible ignorance, were meritorious, then divine grace would flow into these crimes. Do you shudder to hear these things? Yet the Probabilists cannot escape hence. Either they must needs confess works worthy of eternal glory without divine grace — and this is manifest heresy; or they are compelled to concede that man is aided by divine grace to fornicate, to commit adultery, to lie, and to perjure himself, whenever a man with an invincibly erroneous conscience judges it good to lie, to fornicate, to perjure himself, to commit adultery, and the rest.

V. Fr. La-Croix answers, in the place cited, number 29: Every will (he says) good per se is from God as its author — I concede; good per accidens — I deny. More than excellent! A will good per accidens is not from God? A will good per accidens signifies that the will is good not absolutely, but on account of invincible ignorance: for this is the meaning of the phrase per accidens. But this will is truly and really good: since this goodness merits, as the adversaries confess, the reward of eternal life. Therefore there is given a moral goodness, and a reward of eternal life, which is not from God. But hear Fr. Carlo Casnedi, who in Tome I, Disputation 6, section 1, § 3, number 25, page 167, writes as follows: Whenever to a morally invincible ignorance of the prohibition and of the malice there is joined an invincible error concerning the honesty of the object, or concerning a precept of the action, then the work elicited under that ignorance and error is honorable and meritorious. And more openly, in the same place, page 192, he adds: So too there is nothing absurd in Christ the Lord saying: Come, thou blessed one, receive the kingdom, because thou didst lie, invincibly thinking that in such a case I had commanded lying. Do not these things, even barely stated, instill a certain horror?

VI. The Adversaries are pressed in another way. If error possessed this prodigious efficacy, that it could fashion the form of virtue upon vices and crimes, and set round them the laurel of merit, then works honorable, directed by the light of truth, would be of the same dignity as works flagitious, covered over with the darkness of errors. If an erroneous persuasion poured goodness into a depraved operation, in the same way as true knowledge into an honorable work, then enlightenment would be superfluous — superfluous the sermons and exhortations. Finally, no work is good which is not directed by the virtue of prudence. Now between conscience and prudence there is this difference: that conscience, since it is not a virtue, is now true, now false, now right, now criminal; whereas prudence, since by its nature it is a practical intellectual virtue, either is true, or is not prudence — but a mask and specter of prudence. This prudence can never be deceived, although the prudent are sometimes deceived: for if it were deceived, it would not itself be a virtue.

VII. They object, first: he who, erring, judges a feigned pauper to be a true pauper, and succors him, truly exercises a good and meritorious act of mercy. Therefore a work proceeding from invincible ignorance is good. Peter, reputing this man to be his father, is bound to honor him; the Faithful hearing Mass are bound to adore the host, even though it were not consecrated. These and similar examples the Probabilists bring forward to throw dust in the eyes of the unskilled, though they are trifles vainer than Sicilian tales.

VIII. That you may straightway detect the sophism, distinguish the will of succoring the pauper from the will of lying, of perjuring, and the rest. What judgment, then, do you pronounce upon each? Is it not this: the first can be good; not so the second? A man, whether he be poor or rich, carries with him by his nature nothing that impedes the goodness and merit of the alms. For both the rich man, and any man whatever, can beg alms for a good end, and can make himself poor for the sake of Christ. Just as in an indifferent object, so much less in almsgiving is there any malice which impedes the goodness and merit of the act. In lying, on the contrary, in perjury, and in any action depraved by its nature, malice resides intrinsically, which wars as an enemy against goodness and merit. Now the judgment directing the will in the aforesaid case is that dictate which prescribes that the pauper must be succored; and this judgment is true. Furthermore, an act of beneficence towards a man, whoever he be, commanded by charity, is always good and meritorious; but the judgment by which this man, who is in reality rich, is judged poor, is false. Yet this judgment does not direct the will of the alms. Just as in the will there are often evils mixed with goods — not that the same act is both good and evil, for that is chimerical, but because there are found acts good and acts evil, mutually disparate — so also in the intellect false things are mingled with true; but never can a false judgment direct a right will, or an act of virtue. They press on with their quibbling: The matter of almsgiving is poverty; this removed, the virtue of almsgiving collapses. Answer: You are deceived. The object of almsgiving is a man to be relieved; that is, almsgiving looks to this, that it succor a man. If this man is truly poor, the almsgiving is altogether perfect. If this man feigns himself poor, then the almsgiving lacks this prerogative of relieving a pauper. Does it on that account cease to be a good act commanded by charity? He who honors a feigned father does not exercise filial honor, because the object — namely, paternity — is wanting; but he exercises a good act, for he honors a neighbor and an elder. He who adores an unconsecrated host commits an act of material idolatry, which is not imputed to fault, on account of invincible ignorance. But the intention of adoring God is good, nor is it infected by the materially depraved election; for only formal malice infects the act of intention.

IX. They object, secondly: When reason proposes to me anything as a precept, I am bound to execute it. Reason in this case proposes to me that I must lie, or perjure myself, for the salvation of my Neighbor. Therefore I am bound to fulfill this. Answer. All this is true, when the reason, or conscience, is invincibly erring. But whence is it inferred that acts of this kind are good? These acts are in very deed depraved; but they are not imputed to fault, on account of the invincible ignorance.

X. They insist. The lie in this hypothesis is not good. But neither is it evil. Therefore it is an indifferent work. Acts indifferent in the individual are not given: therefore they are either evil or good. Answer. That lie, that perjury, that theft, and the other works depraved by their nature, are always evil, even while they are represented as good; but they are not imputed to fault, as has been said so often, in the hypothesis that the ignorance is invincible. There are no works indifferent in the individual which flow from deliberate reason; but those are indifferent which proceed from necessity.

XI. I pass over many other sophisms, because they are all inept and vain. Read, if you will, Tome 2 of the Apparatus, Dissertation 1, chapter 5, § 2, etc., where you will find all the quibblings of Terillus overthrown.

XII. Sole Question. What is a perplexed conscience? Answer. It is a judgment by which you judge that you sin, whether you choose this part or the other. If the ignorance be vincible, you sin whichever part you choose; and, that sin may be avoided, the judgment must be laid aside, since it is erroneous. But if the ignorance be invincible, and the judgment cannot be laid aside, then that must be chosen which seems the lesser evil, and which less favors one's own liberty and appetites. But these cases are rare, and scarcely ever occur; therefore they need not be discussed at greater length.

VIII. It is true, however, that the adversaries too admit that moral certainty is necessary; but in this they fail, that they teach that this moral certainty can be had by merely verisimilar conjectures, and merely probable reasons. For even granting that a probable opinion produces so much certainty as suffices as a rule of honest action, it does not, for that reason, follow rightly that it produces so much certainty as suffices for swearing that to be true which we opine to be only probable. For a greater certainty is required for an oath than for any moral opinion whatsoever. For this latter, mere true probability suffices to be a rule of honest action. But when someone swears something as true, it is not enough that it be probable; it is required that it appear true to the swearer — not through merely probable reasons, but through most weighty principles, or arguments, and certain ones. When this certainty is lacking, and only conjectures and probable reasons appear, then the swearer ought to affirm, or deny, a matter as probable, not as true.

Caia confesses that she omitted a Mass of obligation. When asked by the confessor whether she omitted it through her own fault, however, she replies that she was ill and had not been permitted by the doctor to leave her room. The confessor clearly perceives that Caia objectively committed no sin, yet that she evidently thinks she sinned because she did not hear Mass on a day of obligation. Hence he is doubtful whether she sinned at least subjectively or not. From this it is asked:

1. What sort of conscience is required for acting honestly?

2. What is an erroneous conscience, and how does it bind?

3. What kind of sin is committed if someone acts against an erroneous conscience?

4. What is to be said concerning the case?

1. What sort of a conscience is required in order to act honestly ?

Before doing anything the conscience of the agent must at least implicitly pass judgment on the morality of the action, so that the agent judges for certain that this action which he contemplates is allowable. Before many of our actions we are not perhaps conscious of forming such a moral judgment, nor is it necessary to do this explicitly, because we ordinarily act from habit; but whenever we act consciously, at any rate an implicit judgment concerning its morality precedes the putting of the action. That judgment must not be a doubting one, but certain at least with the subjective certainty which excludes all prudent doubt about the morality of the action. For all that is not of faith is sin.¹ In this text it is clear from the context that St. Paul understands by faith a conviction that the action is right; in other words, a certain conscience of its morality.

1 Romans xiv. 23.

2. What is an erroneous conscience and how does it oblige?

An erroneous conscience is an erroneous judgment about the morality of an action; it decides that what is wrong is right, or what is right is wrong. As conscience is the subjective rule of conduct and we are bound to follow it, therefore we are bound to follow an erroneous conscience when it is certain and no wise doubtful. If we do not do this, we act against conscience and commit sin. It may be that we have an erroneous conscience on the point through our own fault, inasmuch as we did not care to instruct and educate it aright, or wilfully closed our eyes to the truth. If this was the case, the objective evil which we do through an erroneous conscience is voluntary in the cause and imputable to us, but at the time when it is done it is subjectively right as it is according to conscience.

3. What sort of a sin is committed by acting against an erroneous conscience ?

The sin committed in this case is of that species which it is supposed to belong to by the erroneous conscience. This follows from the fact that even an erroneous conscience is the rule and measure of subjective morality. The species and gravity of the sin are measured by the rule.

4. The case. "Caia confessed that she had omitted Mass on a day of obligation. She had been ill on the day and had been forbidden to go out by her doctor. Of course there was no objective sin, but did she commit sin by going against her erroneous conscience which judged wrongly that the omission was sinful? There was probably some confusion in Caia’s mind; she can hardly have thought that she was committing sin by not hearing Mass when she could not go on account of illness and because the doctor forbade her to go. Even if she thought that she was committing sin, she nevertheless would not do so for want of liberty if she was physically too ill and weak to go. If she could physically go, and if she thought that she was bound to go, she committed a sin of violation of the precept of hearing Mass on account of her erroneous conscience.

97. Thesis XIII. Conscience when certain must be obeyed, whether it be correct or invincibly erroneous.