Look somewhere else for someone who can follow you in your researches about numbers. For my part, I confess that they are far beyond me, and I am competent only to admire them.

If a man loves a woman for her beauty, does he love her? No; for the smallpox, which destroys her beauty without killing her, causes his love to cease. And if any one loves me for my judgment or my memory, does he really love me? No; for I can lose these qualities without ceasing to be.

Thinking too little about things or thinking too much both make us obstinate and fanatical.

Lust is the source of all our actions, and humanity.

I cannot judge my work while I am doing it. I have to do as painters do, stand back and view it from a distance, but not too great a distance. How great? Guess.

[On vanity:] The nose of Cleopatra: if it had been shorter, the face of the earth would have changed.

The weakness of human reason appears more evidently in those who know it not than in those who know it.