[2] 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.
Deliberately fostered ignorance is affected or studied; it can increase guilt.
An action committed in ignorance of the law prohibiting it, or of the facts of the case, is not a voluntary act".
Martin Luther believed that invincible ignorance was only a valid excuse for offenses against human law.
In his view, humans are ignorant of divine law because of original sin, for which all bear guilt.