Chapter IV. The Probable Conscience

A SUBJECTIVELY certain conscience that the proposed action is lawful is required before performing any action, as we have already seen. A great difficulty—a difficulty which has to be faced by all moralists—arises from this principle in consequence of the uncertainty as to whether many actions in the concrete are lawful. One need not consult the works of moralists to find out what difference of opinion there is among experts on many practical questions of morals. It will be sufficient to consult one’s own experience. In the conflict of rights and duties, and in the obscurity which exists as to the application of moral principles to concrete cases, we are frequently at a loss as to what course duty prescribes. The cases which are constantly submitted to the decision of courts of law, but which also belong to morality, illustrate the familiar truth that opinion and not certainty is very often alone attainable in the field of conduct. But if this be the case, what is a conscientious man to do? He finds himself in a difficulty; what the right thing to do under the circumstances may be is not clear. A young man has promised to marry a girl somewhat his inferior in social position; they are both satisfied that the union would be a happy one for both, but the young man’s parents will not hear of the thing, and strictly forbid him to see the girl again. Must he obey his parents, or may he follow his inclinations and keep his promise? He consults those whose knowledge and judgement he respects, and they give him contrary decisions. He goes to recognized authorities on morals, and finds the same difference of opinion.

This example is but a type of innumerable questions which constantly arise in everyday life. Is it possible to lay down any universal principle for the solution of such doubtful cases, so as to be able to act with a certain conscience ?

Catholic theologians answer this question in the affirmative, but they are not agreed as to what the principle is. A probabiliorist would tell the young man that he must obey his parents and break off the engagement unless the opinion that he may marry the girl in spite of the prohibition is distinctly ae more probable than the opposite. An equiprobabilist would say that he may marry the girl if the weight of opinion is fairly equal on either side. A probabilist would maintain that he may marry her if there is a solidly probable opinion which favours that course. The terms are technical, and their meaning should be carefully studied. - An opinion, as we have already gathered from St Thomas, is an adhesion of the mind to one proposition, but with a consciousness that the opposite may be true.

A probable opinion is one which rests on good and solid grounds, such as would incline a man of prudence and judgement to embrace it. If the intrinsic reasons of the opinion are the grounds for embracing it, we have an intrinsic probability; if authority is the ground, we have an extrinsic probability.

A more probable opinion is one which rests on weightier reasons than the opposite, but which leaves the opposite still probable.

A very probable opinion rests on such solid grounds that the opposite is not considered solidly probable.

A morally certain opinion excludes even slight probability in the opposite; it is an adhesion of the mind to a truth without any fear of mistake.

In this difficult question, the Catholic Church so far has been content to condemn extreme views, and allows her children to follow any of the moderate systems mentioned above. Alexander VIII¹ condemned rigorism, which required direct moral certainty in all cases about the lawfulness of an action, and denied that it is ever lawful to follow an opinion which is very probable among several. Laxism was condemned by Innocent XI, since it taught that one might lawfully act on a slight probability.² The systems which are known as Probabiliorism, Equiprobabilism, and Probabilism all have their adherents; the Catholic moralist is free to follow whichever he wishes.

To us it seems that probabilism is the true system, and if it be rightly understood, as it is taught by its moderate supporters, and not as it is misinterpreted by its opponents, we are convinced that it will recommend itself to practical common sense.

Its maxim may be formulated thus: When there is only question of committing sin or not, it is lawful to follow a solidly probable opinion, even though the opposite may be more probable.

The wording of the formula should be carefully weighed. The words “ when there is only question of committing sin or not ” limit the application of the principle to cases where the only question is whether by following such a course sin will be committed because a certain law, human or divine, will be broken. Probabilism, then, cannot be applied to cases where the validity of an act is in question, where some end must be obtained, or where there is question of the certain right of some other person which must be respected. In all these cases we are bound to safeguard the end by taking means that are sure and not merely probable. These are not so many exceptions to the use of probabilism; there is a certain obligation to use secure means to obtain the end in view in such cases, and so there can be no question as to whether probabilism is applicable or not. This will explain why Innocent XI condemned a proposition which asserted that it is not unlawful for a minister of the sacraments to follow a probable opinion about their validity when administering them; and another, which taught that a judge might use probabilism in giving sentence in a court of law; and a third, which excused an infidel who followed a probable opinion and remained in infidelity. In all these cases there is not merely question of sin, but the certain rights of others are at stake, or there is question of an end which cannot lawfully be exposed to risk.

Again, the words “ it is lawful to follow a solidly probable opinion ” should be noted. It is not a question as to what is more perfect, what the noble and generous thing to do may be. The rule merely asserts that there is no obligation under pain of sin to follow the more perfect course, if in the case there be one.

Finally, the words are added “ even though the opposite may be more probable.” For the greater probability of the other view does not make it certain, nor is the supposed greater probability a sure guarantee that the more probable view is the more true. It very frequently happens that an opinion which is considered more probable at one time is thought less probable or altogether improbable at another. Moreover, degrees of probability are very difficult to determine. What seems more probable to one theologian seems less so to another, or even to the same at a different time. And even if it be granted that one opinion is certainly and absolutely more probable, the opposite may for all that remain solidly probable.³ With these provisos the proof of the thesis is not very difficult.

¹ Prop. 3, condemned December 7, 1690.

² Prop. 3, condemned March 2, 1679.

³ Decree of March 2, 1679, props. 1, 2, 4.

Whenever there is a solidly probable opinion that a particular action is lawful, there is no certain law forbidding one to perform it. But it is lawful to do what no certain law forbids. Therefore when there is only question of committing sin or not, it is lawful to follow a solidly probable opinion even though the opposite may be more probable.

The major premise of this syllogism is obvious. No opinion can be probable which has a certain law against it. The certain law imposes a certain obligation. On the other hand, if an opinion is probable and acknowledged as such by five or six experts, good, prudent, and learned men, it is impossible that there should be a law contrary to the probable opinion. Or if there is such a law, the law cannot be sufficiently promulgated, or else it would be known to the experts. But a law which is not sufficiently promulgated does not bind; ignorance excuses from its transgression. The minor premise, too, is clear. We are at liberty to do what no certain law prohibits. If indeed I doubt whether an action is forbidden, I am bound to inquire and satisfy my conscience on the point. But whenever there is a probable opinion, this inquiry has been already made by experts, and with the result that no law forbidding the action can be discovered, otherwise the opinion will not be probable. The conclusion then is certain.

Therefore in cases where there is a probable opinion, or a positively doubtful conscience, I may arrive at a certain conscience required for lawful action by reasoning implicitly somewhat as follows: The opinion is probable that this action which I am contemplating is lawful—for example, marrying according to my promise a good and suitable person in spite of the prohibition of my parents which indeed does not seem to be reasonable. But if this is so, there is no law forbidding me to do it; I violate no obligation in marrying her. Therefore J may marry her.

The proof of probabilism from what we must call at least the toleration of the Church for some centuries will perhaps appeal still more strongly to Catholic minds, The guardianship of faith and morals has been committed to the Church by her divine Founder. He has promised that she shall not fail in the task committed to her even to the end of time. But if a false doctrine is widely held and publicly taught for some centuries in the Church, and she does not condemn it, does not protest against it, the promise of Christ ’ fails to be effective, which is impossible. So that probabilism, which has been widely held and publicly taught for some centuries as a theory of morals without being condemned by the Church, cannot be a false system¹ A third argument may be drawn from the approbation of the works of St Alphonsus Liguori by the Holy See. The decree of May 18, 1803, on the revision and approbation of the works of St Alphonsus with a view to his beatification, gives a list of his works and expressly states that after careful examination nothing reprehensible was found in them. Among the works mentioned is a dissertation on the moderate use of a probable opinion when it conflicts with a more probable opinion on the other side, published in 1755. In this dissertation St Alphonsus clearly and ably defends and proves probabilism; he never withdrew or corrected this dissertation, though to save his Congregation and the doctrine he afterwards modified the statement of his views. He followed probabilism in his choice of opinions while writing his great work on moral theology which subsequently, though he admitted corrections in details, remained substantially the same.

¹ St Alphonsus, Dissertation, anno 1755, n. 10.

It has been already pointed out that, although we may lawfully adopt and follow a probable opinion, there is no obligation of doing so, and it will frequently be more perfect to follow an opposite opinion. It is not intended to propose probabilism as the ideal of Christian conduct; we go to ascetical writers and elsewhere for that.¹ Probabilism is especially an instrument of moral theology, to be wisely and prudently used by the confessor in the confessional, as the doctor uses his medicines in the sick room.

¹ Cf. Rodriguez, On the Practice of Christian and Religious Perfection, i, c. 8.

Theologians warn us that only experts can judge of the intrinsic probability of an opinion. Others must be content to be able to discover extrinsic probable opinions. They can do this by consulting approved authors. If they find that an opinion is held as probable by five or six authors of repute, and it has not become obsolete by new legislation, by decrees of the Holy See, or by the progress of theological opinion, they may act upon it as solidly probable. The Sacred Penitentiary, July 5, 1831, declared that a professor of theology or a confessor might follow in practice the opinions of St Alphonsus.

In thus adopting extrinsically probable opinions with regard to conduct, the priest or the layman only does what anyone not skilled in law would do in a difficult legal case—he would consult an expert whom he could trust.

A limitation to the use of probabilism is mentioned by theologians. When one has decided on any course of conduct, he must loyally adhere to the consequences which the decision involves. He must not use a probable opinion to gain an advantage, and then in the same matter adopt the contrary opinion in order to shake off a burden. And so when a probable opinion has been adopted in favour of the validity of a will in my behalf, I cannot also adopt a contrary opinion that the will is invalid and refuse to pay the legacies,