§ I. On Ignorance

10. Definition. - Ignorance, taken generally, is the lack of knowledge.

Division. - Ignorance is distinguished:

1° On the part of the subject, into positive (or privative) and negative (or nescience), according as it is the lack of knowledge owed, or of knowledge not owed, for example ignorance of canon law in a countryman. Each differs from error; for the latter denotes a discrepancy between that which the mind judges and the thing concerning which it judges. Thus, with respect to a usurious contract, he labors under ignorance who does not know it to be usurious (lack of cognition); but he labors under error who, although he knows it to be usurious, nevertheless judges it lawful. Therefore every error is ignorance, but not conversely. How error differs from fraud, see n. 882. 3°.

2° On the part of the object, into ignorance of law and of fact, according as it is concerned with the existence of a law, or of a particular fact.

3° On the part of the cause, or of the will from which it proceeds, into vincible and invincible, according as, with diligence applied, it can be overcome or not. - But invincible ignorance is physically such, if in no way it can be overcome; morally such, if, after moral diligence has been applied, it cannot be removed.¹

But that diligence is judged moral which prudent persons, according to the gravity of the matter and according to their own capacity, in such circumstances, are wont to employ.¹

4° On the part of the action which is done from ignorance, one kind is antecedent, which is in no way willed and is the cause of the work, so that, if the ignorance itself were not present, the work would not be done; as if someone pierces a man whom he invincibly thinks to be a wild beast, and would not have killed him unless he had been ignorant that he was a man. Another kind is concomitant, which neither is voluntary, nor is the cause of the work, so that, although it were absent, the work would equally be done; as if someone, invincibly thinking that he is killing a wild beast, kills a man long sought for death, whom he would also have killed if he had known him. Another kind is consequent, which in some way follows an act of the will unwilling or negligent to inquire, and is directly or indirectly willed; and therefore it is otherwise called vincible ignorance. Haine, ib. p. 11. q. 27.

Vincible ignorance is distinguished in three ways, namely: 1° simply such, when some diligence, yet not sufficient diligence, is applied to dispel it; 2° crass or supine, when no, or scarcely any, zeal is put into investigating the truth; 3° affected, when someone voluntarily shuns the means of laying aside ignorance, lest he be drawn back from his own purpose.

To invincible ignorance perfect forgetfulness and full inadvertence must be referred. But these, if they are not perfect, or if they proceed from culpable negligence, belong to vincible ignorance.

11. Principles. - I. Invincible ignorance entirely takes away the voluntary, both because it itself is not voluntary, and because nothing can be voluntary where there is no cognition. Therefore no act proceeding from invincible ignorance can be imputed to the agent. Thus likewise one must determine concerning perfect forgetfulness and inadvertence, since the same reason obtains. - Antecedent ignorance precisely causes the involuntary, and indeed positively, because, if knowledge were present, the act would not be placed.

II. Vincible ignorance does not take away the voluntary. For ignorance of this sort, whether directly or indirectly, is truly voluntary. Nevertheless it diminishes the voluntary, because it is the cause of willing that which, if it were absent, one is supposed never to have willed. The same also, by parity of reason, say concerning imperfect forgetfulness and inadvertence, and also concerning consequent ignorance.

III. Crass ignorance and affected ignorance diminish the voluntary much less, and consequently sin. The reason is that the former arises from grave negligence, while the latter is retained deliberately for sinning more freely, and therefore is an indication of a very intense voluntary, under which respect it also increases the sin. S. Th., De malo, q. 3. a. 7.

IV. Concomitant ignorance causes the involuntary, but only negatively, or the non-voluntary, not positively, because it is not against the inclination of the will; for the agent rejoices when he notices it. Hence it does not wholly excuse from sin, because it does not take away every habitual or actual conditioned will of sinning; nor again does it wholly cause sin, because it is involuntary and invincible. Hence he who from such ignorance kills, as if it were a wild beast, a cleric who is his enemy, remains guilty of internal homicide because of the evil will of killing his enemy, if he had known him; nevertheless he is excused from external homicide, nor does he incur excommunication, irregularity, or restitutions; because an external act not voluntarily placed does not induce these penalties, and an internal act does not induce them. Haine, ib. p. 13. q. 29.

Resolutions. - 1° Children who have done things illicit in themselves without any pang of conscience or suspicion of malice did not formally sin in reality, even if they had already attained the use of reason; and therefore afterwards they are not bound to confess them, when they understand those things to be illicit, since material sins are not matter for confession.

2° If a confessor or judge notices that he lacks sufficient knowledge to discharge his office as is fitting, and neglects to acquire knowledge, or before he has acquired it continues to exercise his office, he will be held for the errors which he foresaw at least in some way, because they are voluntary to him, at least in their cause.

3° Those who through their own fault are not accustomed to hear Mass on Sundays and are little solicitous about the feasts and fasts to be observed, as such persons have become accustomed, are not excused from sin if they do not observe the feasts and fasts, on the ground that they are ignorant of them; for the ignorance is vincible, since they voluntarily neglect to apply the means by which they could know them. But if only once or twice they have omitted Mass, whether with or without their own fault, and have not even suspected that a feast day or day of fasting was occurring during the week, they are excused from sin, since their ignorance is invincible; for he cannot be called voluntarily negligent in applying the means of dispelling ignorance who does not even think about applying them. - Likewise they sin who, dwelling in the country, far from a church, have neglected to inquire from books, or, if they do not know how to read, from others, for example Catholic neighbors, concerning feasts and fasts. But those are excused who, unskilled in reading and living among non-Catholics, have no one to admonish them concerning these things. The reason for both is the same as that which was brought forward just now.

4° If negligence in laying aside ignorance is culpable only venially, the deed following from it will be imputable only to venial fault. The reason is that acts of this sort are voluntary and therefore culpable only in their cause; therefore, since the cause, namely ignorance, does not reach grave fault, the effect cannot exceed light fault.

5° Vincible ignorance of a thing knowledge of which is prescribed by reason of itself (for example, of the mysteries of Faith, n. 257 sqq.) is a sin specifically distinct from that which is done from ignorance of this sort; because one sinning in this way acts against two diverse precepts issued for a diverse motive (n. 213). But if cognition is prescribed only by accident, by reason of the work to be done, it is not a special sin, but only one sin against that virtue

to which belongs the observance of the precept that is vincibly ignored. For by the same precept by which I am bound, for example, to fast, I am also bound to inquire. Hence, if through negligence in inquiring I do not fast, it is enough if I confess: I violated the fast. Haine, ib. p. 14. q. 31.

See many other things concerning ignorance elsewhere passim, especially in the treatise on Conscience, on Laws, on Sins, and on Contracts in general, where error is treated.