“ Whether it is proper to the unjust man to do unjust deeds? ”
 Thomas Aquinas, Summa Theologica (1274). copy citation

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“Although fortitude is about the most difficult things, it is not about the best, for it is only useful in warfare, whereas justice is useful both in war and in peace, as stated above. _______________________ QUESTION 59 OF INJUSTICE (In Four Articles) We must now consider injustice, under which head there are four points of inquiry: (1) Whether injustice is a special vice? (2) Whether it is proper to the unjust man to do unjust deeds? (3) Whether one can suffer injustice willingly? (4) Whether injustice is a mortal sin according to its genus? _______________________ FIRST ARTICLE [II-II, Q. 59, Art. 1] Whether Injustice Is a Special Virtue?” source