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.

To find recreation in amusement is not happiness.

Man is so made that by continually telling him he is a fool he believes it, and by continually telling it to himself he makes himself believe it. For man holds an inward talk with himself, which it pays him to regulate.

What matters it that man should have a little more knowledge of the universe? If he has it, he gets little higher. Is he not always infinitely removed from the end, and is not the duration of our life equally removed from eternity, even if it lasts ten years longer?

Men are so necessarily mad, that not to be mad would amount to another form of madness.

The arithmetical machine produces effects that approach nearer to thought than all the actions of animals. But it does nothing that would enable us to attribute will to it, as to the animals.

The greater intellect one has, the more originality one finds in men. Ordinary persons find no difference between men.