I have come to realize that an early symptom of approaching mental illness is the belief that one's work is terribly important. If you consider your work very important you should take a day off.

It is impossible to read in America, except on a train, because of the telephone. Everyone has a telephone, and it rings all day and most of the night.

Adventurous men enjoy shipwrecks, mutinies, earthquakes, conflagrations, and all kinds of unpleasant experiences. They say to themselves, for example, 'So this is what an earthquake is like,' and it gives them pleasure to have their knowledge of the world increased by this new item.

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.

Morally, a philosopher who uses his professional competence for anything except a disinterested search for truth is guilty of a kind of treachery.

For some reason which I have failed to understand, many people like the system [scientific totalitarianism] when it is Russian but disliked the very same system when it was German. I am compelled to think that this is due to the power of labels; these people like whatever is labelled ‘Left’ without examining whether the label has any justification.

Science has made unrestricted national sovereignty incompatible with human survival. The only possibilities are now world government or death.