Ignorance and error are necessary to life, like bread and water.

In order that knowledge be properly digested it must have been swallowed with a good appetite.

To die for an idea is to set a rather high price upon conjecture.

Dog! When we first met on the highway of life, we came from the two poles of creation.... What can be the meaning of the obscure love for me that has sprung up in your heart?

I do not know any reading more easy, more fascinating, more delightful than a catalogue.

Devout believers are safeguarded in a high degree against the risk of certain neurotic illnesses; their acceptance of the universal neurosis spares them the task of constructing a personal one.

It is by acts and not by ideas that people live.