Vincible ignorance

Vincible ignorance is, in Catholic ethics, ignorance that a person could remove by applying reasonable diligence in the given set of circumstances. It contrasts with invincible ignorance, which a person is either entirely incapable of removing, or could only do so by supererogatory efforts (i.e., efforts above and beyond normal duty). An example of vincible ignorance would be a person who is unsure about certain Catholic teachings, but refrains from seeking an explanation of those teachings.

While invincible ignorance eliminates culpability, vincible ignorance at most mitigates it, and may even aggravate guilt. The guilt of an action performed in vincible ignorance ought to be measured by the degree of diligence or negligence shown in performing the act. If some insufficient diligence was shown in dispelling ignorance, it is termed merely vincible; it may diminish culpability to the point of rendering a sin venial. When little or no effort is made to remove ignorance, the ignorance is termed crass or supine; it removes little or no guilt. Deliberately fostered ignorance is affected or studied; it can increase guilt.

Ignorance ought to be distinguished from mere nescience. Ignorance is a lack of knowledge that a person has a duty or obligation to know, whereas nescience refers to a lack of knowledge about things one is not bound to know. Thus vincible and invincible ignorance only can be applied to matters that a person has a duty to know about. For example, if a doctor did not know the name of a certain artery in the body, he would be ignorant of that information, but the rest of the population who has no duty to know that information would be nescient of it.

Ignorance may be

 This article incorporates text from a publication now in the public domain: Herbermann, Charles, ed. (1913). "". Catholic Encyclopedia. New York: Robert Appleton. 

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