So long as a man imagines that he cannot do this or that, so long as he is determined not to do it; and consequently so long as it is impossible to him that he should do it.

Hatred is increased by being reciprocated, and can on the other hand be destroyed by love.

If men were born free, they would, so long as they remained free, form no conception of good and evil.

Be not astonished at new ideas; for it is well known to you that a thing does not therefore cease to be true because it is not accepted by many.

The safest way for a state is to lay down the rule that religion is comprised solely in the exercise of charity and justice, and that the rights of rulers in sacred, no less than in secular matters, should merely have to do with actions, but that every man should think what he likes and say what he thinks.

Philosophy has no end in view save truth; faith looks for nothing but obedience and piety.

I have tried sedulously not to laugh at the acts of man, nor to lament them, nor to detest them, but to understand them.