The most dangerous madmen are those created by religion, and people whose aim is to disrupt society always know how to make good use of them on occasion.

Posterity for the philosopher is what the other world is for the religious man.

I feel, I think, I judge; therefore, a part of organized matter like me is capable of feeling, thinking, and judging.

The good of the people must be the great purpose of government. By the laws of nature and of reason, the governors are invested with power to that end. And the greatest good of the people is liberty. It is to the state what health is to the individual.

Does anyone really know where they're going to?

The arbitrary rule of a just and enlightened prince is always bad. His virtues are the most dangerous and the surest form of seduction: they lull a people imperceptibly into the habit of loving, respecting, and serving his successor, whoever that successor may be, no matter how wicked or stupid.

One must be oneself very little of a philosopher not to feel that the finest privilege of our reason consists in not believing in anything by the impulsion of a blind and mechanical instinct, and that it is to dishonour reason to put it in bonds as the Chaldeans did. Man is born to think for himself.