To remain ignorant of history is to remain forever a child
Nihil est incertius vulgo, nihil obscurius voluntate hominum, nihil fallacius ratione tota comitiorum. (Nothing is more unpredictable than the mob, nothing more obscure than public opinion, nothing more deceptive than the whole political system.)
Be a pattern to others and then all will go well.
No one has leave to sin.
The remembrance of past misery is sweet.
It is a crime to put a Roman citizen in chains, it is an enormity to flog one, sheer murder to slay one: what, then, shall I say of crucifixion? It is impossible to find the word for such an abomination.