The deepest definition of youth is life as yet untouched by tragedy.

Order is not sufficient. What is required, is something much more complex. It is order entering upon novelty; so that the massiveness of order does not degenerate into mere repetition; and so that the novelty is always reflected upon a background of system.

Faith in the possibility of science, generated antecedently to the development of modern scientific theory, is an unconscious derivative from medieval theology.

You cannot evade quantity. You may fly to poetry and music, and quantity and number will face you in your rhythms and your octaves.

Life is the enjoyment of emotion, derived from the past and aimed at the future.

No period of history has ever been great or ever can be that does not act on some sort of high, idealistic motives, and idealism in our time has been shoved aside, and we are paying the penalty for it.

No science can be more secure than the unconscious metaphysics which tacitly it presupposes.