Sometimes people do things on the basis of mistakes of fact; they would have acted otherwise had they known better. One has a moral obligation to try to determine facts in important matters, and also to proceed on the safe side in guesses about factual matters when important moral obligations are to be fulfilled (see 12‑B). However, one can and often does make mistakes of fact. In cases of this sort, the judgment of conscience based on false information is not itself in error.
For example, a woman takes what she thinks to be a safe sleeping pill, prescribed by her doctor, because she is restless during the early weeks of pregnancy. The pill turns out to cause severe, congenital defects in the child whom she wished only to protect by caring for her own health. Had she only known, she would have done otherwise. However, her conscientious decision to go to a physician about her difficulties in early pregnancy and to follow the prescription she received was perfectly sound. The error was not at all in conscience.
The error of fact can be about a moral fact. For example, a child is sent by parents to what is recommended as an excellent Catholic school. The parents decide to do this at great sacrifice out of a sense of duty, because of the bad moral atmosphere of the local public school. At the Catholic school, some of the teachers who are depraved seduce the child. The parents wrongly feel somehow at fault.
It is easy for persons who are developing a genuine conscience to mistake the deliverances of superego or social convention for moral truths. For example, some good Germans who had developed but imperfectly integrated consciences rightly judged (as a matter of moral truth) that they had to resist certain Nazi decrees, yet felt guilty and unpatriotic about it. In some matters, these lower levels of conscience probably confused their judgments, so that they did not see clearly how little responsibility they had toward that regime. Thus they were restrained from more bold action by blameless confusion of conscience.
Within the sphere of moral reasoning itself, blameless errors also are possible. For example, one can easily absolutize a nonabsolute norm, failing to notice that additional intelligible factors call for reconsideration. Again, one can notice that an action is consistent with several basic principles of morality and mistakenly conclude it is morally right, although further inquiry would have indicated that it is not. For instance, one who notices that killing in self-defense is not otherwise immoral might consider it justified in a case in which a Christian should accept death rather than kill in self-defense.
To the extent that one must supplement one’s moral reasoning by appeal to a moral authority, one tends to perceive the norms proposed by that authority as if they were rules of law. Most Catholics thus rely upon the Church’s teaching for normative guidance in some matters in which the norm proposed would not in itself be recognized as a moral truth. This situation is a necessary stage in the development of a fully mature Christian conscience—a stage from which most of us never totally emerge. However, it has its own hazards, which create possibilities of innocent mistakes.
Specific norms which are proposed can be misunderstood. For example, people easily misunderstand the commandment to obey proper authority, not observing that the authority must operate within its due bounds (see S.t., 2–2, q. 104, a. 5). Conversely, they easily misunderstand the duty to make exceptions in the fulfilling of laws, thinking this to be a right to exempt oneself whenever one honestly thinks the lawmaker, if informed of the facts, would consider an exception reasonable (see S.t., 1–2, q. 96, a. 6; 2–2, q. 120, a. 1). Thus, people often are both too strict and too lax, too subservient to laws and not sufficiently submissive to them.
Perhaps even more important, one who looks to a moral authority needs procedural rules for determining in doubtful cases when the authority is proposing a binding norm and what this norm is. This is the role fulfilled by probabilism and the other moral systems. One such procedural rule is: If there is a real doubt whether a binding norm has been proposed, then one is not morally obliged to assume that it has been: “A doubtful law does not oblige.”
This procedural rule (explained in 12‑D) presupposes that one has tried to resolve the doubt by investigation and that the doubt is within the framework of the Church’s teaching. However, people informed of this maxim in the course of superficial moral guidance often misunderstand it to mean that moral matters debated by theologians automatically become open questions, so that the norms lose their force.
Even in the cases discussed here, “blameless” mistakes are not always in fact completely blameless. One perhaps failed somewhere to do something one could and should have done; one perhaps was in too much of a hurry to deal with a certain matter and did not give it quite enough attention. However, such faults would be venial sins. Perhaps there is little or no moral error without a basis somewhere in at least a venial sin.