Scepticism is the first step toward truth.

It seems to me that if one had kept silence up to now regarding religion, people would still be submerged in the most grotesque and dangerous superstition ... regarding government, we would still be groaning under the bonds of feudal government ... regarding morals, we would still be having to learn what is virtue and what is vice. To forbid all these discussions, the only ones worthy of occupying a good mind, is to perpetuate the reign of ignorance and barbarism.

If your little savage were left to himself and be allowed to retain all his ignorance, he would in time join the infant's reasoning to the grown man's passion, he would strangle his father and sleep with his mother.

He whom we call a gentleman is no longer the man of Nature.

There is not a Musselman alive who would not imagine that he was performing an action pleasing to God and his Holy Prophet by exterminating every Christian on earth, while the Christians are scarcely more tolerant on their side.

Integrity is the evidence of all civil virtues.

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.