To stimulate creativity one must develop childlike inclination for play and the childlike desire for recognition.

For science can only ascertain what is, but not what should be, and outside of its domain value judgments of all kinds remain necessary. Religion, on the other hand, deals only with evaluations of human thought and action: it cannot justifiably speak of facts and relationships between facts.

I very rarely think in words at all. A thought comes, and I may try to express in words afterwards.

As the area of light expands, so does the perimeter of darkness.

Logic can take you from point A to point B. Imagination can take you wherever you want

I refuse to engage in an intellectual battle with an unarmed man.

[Max Planck] was one of the finest people I have ever known... but he really didn't understand physics, [because] during the eclipse of 1919 he stayed up all night to see if it would confirm the bending of light by the gravitational field. If he had really understood [general relativity], he would have gone to bed the way I did