The true contrast between science and religion is that science unites the world and makes it possible for people of widely differing backgrounds to work together and to cooperate. Religion, on the other hand, by its very claim to know “The Truth” through “revelation,” is inherently divisive and a creator of separatism and hostility.

The landscape has been so totally changed, the ways of thinking have been so deeply affected, that it is very hard to get hold of what it was like before… It is very hard to realize how total a change in outlook Isaac Newton has produced.

Our humanist attitude should therefore throughout be to stress what we all have in common with each other and relegate quarrelsome religion to the private domain where it can do [less] harm.

... an opportunity to allow the bees in one's bonnet to buzz even more noisily than usual.

The test of science is not whether you are reasonable—there would not be much of physics if that was the case—the test is whether it works. And the great point about Newton’s theory of gravitation was that it worked, that you could actually say something about the motion of the moon without knowing very much about the constitution of the Earth.

A theory is scientific only if it can be disproved. But the moment you try to cover absolutely everything the chances are that you cover nothing.

Time is that which is manufactured by clocks.