The safest general characterization of the European philosophical tradition is that it consists of a series of footnotes to Plato.

I would be a billionaire if I was looking to be a selfish boss. That's not me.

Now in creative thought common sense is a bad master. Its sole criterion for judgement is that the new ideas shall look like the old ones. In other words it can only work by suppressing originality.

Inventive genius requires pleasurable mental activity as a condition for its vigorous exercise

The only use of knowledge of the past is to equip us for the present.

Life is complex in its expression, involving more than percipience, namely desire, emotion, will, and feeling.

I regret that it has been necessary for me in this lecture to administer a large dose of four-dimensional geometry. I do not apologize, because I am really not responsible for the fact that nature in its most fundamental aspect is four-dimensional. Things are what they are.