Private passions grow tired and wear themselves out; political passions, never.

It is because of the servility of photography that I am fundamentally contemptuous of this chance invention which will never be an art but which plagiarizes nature by means of optics. (1848)

Every time that a people which has long crouched in slavery and ignorance is moved to its lowest depths there appear monsters and heroes, prodigies of crime and prodigies of virtue.

To love for the sake of being loved is human, but to love for the sake of loving is angelic.

We don't have two hearts, one for animals and one for humans ; we have one heart or we don't have any.

The impartiality of history is not that of the mirror, which merely reflects objects, but of the judge, who sees, listens, and decides.

Brutality to an animal is cruelty to mankind - it is only the difference in the victim.