Don't believe the results of experiments until they're confirmed by theory.

In the most modern theories of physics probability seems to have replaced aether as "the nominative of the verb 'to undulate'."

An ocean traveler has even more vividly the impression that the ocean is made of waves than that it is made of water.

So far as physics is concerned, time's arrow is a property of entropy alone.

It is one thing for the human mind to extract from the phenomena of nature the laws which it has itself put into them; it may be a far harder thing to extract laws over which it has no control. It is even possible that laws which have not their origin in the mind may be irrational, and we can never succeed in formulating them.

Oh leave the Wise our measures to collate. One thing at least is certain, light has weight. One thing is certain and the rest debate. Light rays, when near the Sun, do not go straight.

I ask you to look both ways. For the road to a knowledge of the stars leads through the atom; and important knowledge of the atom has been reached through the stars.