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

The endeavor to understand is the first and only basis of virtue.

He who has a true idea, knows at that same time that he has a true idea, nor can he doubt concerning the truth of the thing.

Sin cannot be conceived in a natural state, but only in a civil state, where it is decreed by common consent what is good or bad.

No to laugh, not to lament, not to detest, but to understand.

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

The more a government strives to curtail freedom of speech, the more obstinately is it resisted; not indeed by the avaricious, ... but by those whom good education, sound morality, and virtue have rendered more free.