The known is finite, the unknown infinite; intellectually we stand on an islet in the midst of in illimitable ocean of inexplicability. Our business in every generation is to reclaim a little more land.

It is the customary fate of new truths to begin as heresies and to end as superstitions.

There is a thing called knowledge of the world, which people do not have until they are middle-aged. It is something which cannot be taught to younger people, because it is not logical and does not obey laws that are constant. It has no rules.

If a little knowledge is dangerous, where is a man who has so much as to be out of danger?

The medieval university looked backwards; it professed to be a storehouse of old knowledge. The modern university looks forward, and is a factory of new knowledge.

Someone said, 'The dead writers are remote from us because we know so much more than they did.' Precisely, and they are that which we know.