An invincible error is, in Christian philosophy

Christian philosophy

Christian philosophy may refer to any development in philosophy that is characterised by coming from a Christian tradition.- Origins of Christian philosophy :...

, a normally sinful action

Sin

In religion, sin is the violation or deviation of an eternal divine law or standard. The term sin may also refer to the state of having committed such a violation. Christians believe the moral code of conduct is decreed by God In religion, sin (also called peccancy) is the violation or deviation...

 which is not considered sinful because it was committed through blameless ignorance that one's actions were harmful or otherwise prohibited.

In the stated philosophy, a sin occurs when a person knowingly commits an evil act, meaning that they must know both:

• that they are committing the act
• that the act is evil

If a person is ignorant of one of these two facts, then the type of ignorance becomes important. If the person is intentionally or willfully ignorant, this is known as vincible ignorance

Vincible ignorance

Vincible ignorance is, in Catholic ethics, a moral or doctrinal matter that could have been removed by diligence reasonable to the circumstances. It contrasts with invincible ignorance, which can not be removed at all, or only by supererogatory efforts Vincible ignorance is, in Catholic ethics, a...

, and the act is still considered a sin. If, however, the person is unintentionally ignorant of one of these two key facts, then they are considered invincibly ignorant, and have committed an invincible error.