To my mind, to kill in war is not a whit better than to commit ordinary murder.

No one must think that Newton’s great creation can be overthrown in any real sense by this [Theory of Relativity] or by any other theory. His clear and wide ideas will for ever retain their significance as the foundation on which our modern conceptions of physics have been built.

Genius abhors consensus because when consensus is reached, thinking stops. Stop nodding your head.

The true definition of madness is repeating the same action, over and over, hoping for a different result.

Genius simply cannot be reduced to a set of rules for anyone to follow.

This is a time, when there seems to be a particular need for friends of wisdom and truth to join together.

This is too difficult for a mathematician. It takes a philosopher. The hardest thing in the world to understand is the income tax.