Aristotle could have avoided the mistake of thinking that women have fewer teeth than men, by the simple device of asking Mrs. Aristotle to keep her mouth open while he counted.

Very few men can be genuinely happy in a life involving continual self-assertion against the skepticism of the mass of mankind, unless they can shut themselves up in a coterie and forget the cold outer world. The man of science has no need of a coterie, since he is thought well of by everybody except his colleagues. The artist, on the contrary, is in the painful situation of having to choose between being despised and being despicable.

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

Always remember that true happiness is not in getting what you want, but wanting what you already have. He who dies with the most toys is still dead. What is wanted is not the will to believe, but the will to find out, which is the exact opposite.

Protestants, from the first, have been distinguished from their opponents by what they do not believe; to throw over one more dogma is, therefore, merely to carry the movement one stage further. Moral fervor is the essence of the matter.

There is no need to worry about mere size. We do not necessarily respect a fat man more than a thin man. Sir Isaac Newton was very much smaller than a hippopotamus, but we do not on that account value him less.

One must care about a world one will not see.