He who is slowest in making a promise is most faithful in its performance.

Perhaps adversity is a great teacher, but he charges a high price for his lessons, and often the profit we take from them is not worth the price they have cost us.

One advantage resulting from virtuous actions is that they elevate the mind and dispose it to attempt others more virtuous still.

Astronomy was born of superstition; eloquence of ambition, hatred, falsehood, and flattery; geometry of avarice; physics of an idle curiosity; and even moral philosophy of human pride. Thus the arts and sciences owe their birth to our vices.

The social contract.

Man was born free, and everywhere he is in chains.

To write a good love letter, you ought to begin without knowing what you mean to say, and to finish without knowing what you have written.