Calculus required continuity, and continuity was supposed to require the infinitely little; but nobody could discover what the infinitely little might be.

Science does not aim at establishing immutable truths and eternal dogmas; its aim is to approach the truth by successive approximations, without claiming that at any stage final and complete accuracy has been achieved.

Gradually, ... the aspect of science as knowledge is being thrust into the background by the aspect of science as the power of manipulating nature. It is because science gives us the power of manipulating nature that it has more social importance than art. Science as the pursuit of truth is the equal, but not the superior, of art. Science as a technique, though it may have little intrinsic value, has a practical importance to which art cannot aspire.

It is not by delusion, however exalted, that mankind can prosper, but only by unswerving courage in the pursuit of truth.

Modern definitions of truth, such as those as pragmatism and instrumentalism, which are practical rather than contemplative, are inspired by industrialisation as opposed to aristocracy.

Boredom is... a vital problem for the moralist, since half the sins of mankind are caused by the fear of it.

The law of causality, I believe, like much that passes muster among philosophers, is a relic of a bygone age, surviving, like the monarchy, only because it is erroneously supposed to do no harm.