A theory is the more impressive the greater the simplicity of its premises is, the more different kinds of things it relates, and the more extended its area of applicability.

As a human being, one has been endowed with just enough intelligence to be able to see clearly how utterly inadequate that intelligence is when confronted with what exists.

Truly novel inventions emerge only in one's youth. Later one becomes ever more experienced, famous-and foolish.

It is very difficult to explain this feeling to anyone who is entirely without it, especially as there is no anthropomorphic conception of God corresponding to it. The individual feels the nothingness of human desires and aims and the sublimity and marvelous order which reveal themselves both in Nature and in the world of though. He looks upon individual existence as a sort of prison and wants to experience the universe as a single significant whole.

Every reminiscence is colored by the way things are today, and therefore by a delusive point of view.

The restriction of knowledge to an elite group destroys the spirit of the society and leads to its intellectual impoverishment.

I believe that the first step in the setting of a real external world is the formation of the concept of bodily objects and of bodily objects of various kinds.