Boredom is... a vital problem for the moralist, since half the sins of mankind are caused by the fear of it.

The modern man thinks that everything ought to be done for the sake of something else, and never for its own sake.

Do not fear to be eccentric in opinion, for every opinion now accepted was once eccentric.

If I were granted omnipotence, and millions of years to experiment in, I should not think Man much to boast of as the final result of all my efforts.

... mathematical knowledge ... is, in fact, merely verbal knowledge. "3" means "2+1", and "4" means "3+1". Hence it follows (though the proof is long) that "4" means the same as "2+2". Thus mathematical knowledge ceases to be mysterious.

The Axiom of Choice is necessary to select a set from an infinite number of socks, but not an infinite number of shoes.

All human activity is prompted by desire.