Men as a rule pardon all their own faults, make no allowance for others, and fix the whole blame upon the individual, without any regard for the circumstances of the case.
Familiare est hominibus omnia sibi ignoscere, nihil aliis remittere; et invidiam rerum non ad causam, sed ad voluntatem personasque dirigere.
Original text (Latin)
Notes from Wikiquote
2, 30, 3.