Physical concepts are free creations of the human mind, and are not, however it may seem, uniquely determined by the external world.

It is entirely possible that behind the perception of our senses, worlds are hidden of which we are unaware.

I once thought that if I could ask God one question, I would ask how the universe began, because once I knew that, all the rest is simply equations. But as I got older I became less concerned with how the universe began. Rather, I would want to know why he started the universe. For once I knew that answer, then I would know the purpose of my own life.

The great need to grasp principles had caused me to spend most of my time on fruitless persuits.

Those who believe that politics and religion do not mix, understand neither.

What I see in Nature is a magnificent structure that we can comprehend only very imperfectly, and that must fill a thinking person with a feeling of humility. This is a genuinely religious feeling that has nothing to do with mysticism.

The supreme task of the physicist is to arrive at those universal elementary laws from which the cosmos can be built up by pure deduction. There is no logical path to these laws; only intuition, resting on sympathetic understanding of experience, can reach them.