Just as a poet often has license from the rules of grammar and pronunciation, we should like to ask for 'physicists' license from the rules of mathematics in order to express what we wish to say in as simple a manner as possible.

It is surprising that people do not believe that there is imagination in science. It is a very interesting kind of imagination, unlike that of the artist. The great difficulty is in trying to imagine something that you have never seen, that is consistent in every detail with what has already been seen, and that is different from what has been thought of; furthermore, it must be definite and not a vague proposition. That is indeed difficult.

The problem of creating something new, but which is consistent with everything which has been seen before, is one of extreme difficulty.

To those who do not know mathematics it is difficult to get across a real feeling as to the beauty, the deepest beauty, of nature ... If you want to learn about nature, to appreciate nature, it is necessary to understand the language that she speaks in.

God was invented to explain mystery. God is always invented to explain those things that you do not understand.

The beauty that is there is also available for me, too. But I see a deeper beauty that isn't so readily available to others.... I don't see how studying a flower ever detracts from its beauty. It only adds

The test of all knowledge is experiment. Experiment is the sole judge of scientific truth.