That which endures is not one or another association of living forms, but the process of which the cosmos is the product, and of which these are among the transitory expressions.

There is the greatest practical benefit in making a few failures early in life.

I am too much of a sceptic to deny the possibility of anything...

Only a scientific people can survive in a scientific future.

As to sagacity, I should say that his judgement respecting the warmest place and the softest cushion in a room is infallible, his punctuality at meal times is admirable, and his pertinacity in jumping on people's shoulders till they give him some of the best of what is going, indicates great firmness.

If the twentieth century is to be better than the nineteenth, it will be because there are among us men who walk in Priestley's footsteps....To all eternity, the sum of truth and right will have been increased by their means; to all eternity, falsehoods and injustice will be the weaker because they have lived.

Science and literature are not two things, but two sides of one thing.