Abstract work, if one wishes to do it well, must be allowed to destroy one's humanity; one raises a monument which is at the same time a tomb, in which, voluntarily, one slowly inters oneself.

The psychology of adultery has been falsified by conventional morals, which assume, in monogamous countries, that attraction to one person cannot coexist with affection for another. Everybody knows that this is untrue.

If you question any candid person who is no longer young, he is very likely to tell you that, having tasted life in this world, he has no wish to begin again as a "new boy" in another.

As soon as we abandon our own reason, and are content to rely upon authority, there is no end to our troubles.

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

Understanding human nature must be the basis of any real improvement in human life. Science has done wonders in mastering the laws of the physical world, but our own nature is much less understood, as yet, than the nature of stars and electrons. When science learns to understand human nature, it will be able to bring a happiness into our lives which machines and the physical sciences have failed to create.

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.