But no one is deemed to be ignorant of the principles of the moral law, which are written in the conscience of every man.
the promptings of feelings and passions can also diminish the voluntary and free character of the offense, as can external pressures or pathological disorders (mental illness).
(Article 1859 of The Catechism Of The Catholic Church specifies;) "Mortal sin requires full knowledge and complete consent.
It presupposes knowledge of the sinful character of the act, of its opposition to God's law.
Feigned ignorance and hardness of heart do not diminish, but rather increase, the voluntary character of a sin."