The only use of knowledge of the past is to equip us for the present.

From the moment of birth we are immersed in action, and can only fitfully guide it by taking thought.

Nature, even in the act of satisfying anticipation, often provides a surprise.

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

There is no more common error than to assume that, because prolonged and accurate mathematical calculations have been made, the application of the result to some fact of nature is absolutely certain.

It is the business of future to be dangerous.... The major advances in civilization are processes that all but wreck the societies in which they occur.

The way in which the persecution of Galileo has been remembered is a tribute to the quiet commencement of the most intimate change in outlook which the human race had yet encountered. Since a babe was born in a manger, it may be doubted whether so great a thing has happened with so little stir