In order to acquire learning, we must first shake ourselves free of it.

It is the business of the future to be dangerous; and it is among the merits of science that it equips the future for its duties.

The vitality of thought is in adventure. Ideas won't keep. Something must be done about them. When the idea is new, its custodians have fervor, live for it, and if need be, die for it.

Now in creative thought common sense is a bad master. Its sole criterion for judgement is that the new ideas shall look like the old ones. In other words it can only work by suppressing originality.

On the ostensible exactitude of certain branches of human knowledge, including mathematics. The exactness is a fake.

Vigorous societies harbour a certain extravagance of objectives.

In modern times the belief that the ultimate explanation of all things was to be found in Newtonian mechanics was an adumbration of the truth that all science, as it grows towards perfection, becomes mathematical in its ideas.