Despite my being an old gypsy there is a tendency to respectability inherent in old age.

The content of scientific theory itself offers no moral foundation for the personal conduct of life.

I never teach my pupils, I only attempt to provide the conditions in which they can learn.

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.

You can't solve problems with the same thinking that caused them.

I am neither especially clever nor especially gifted. I am only very, very curious.

We owe a lot to the Indians, who taught us how to count, without which no worthwhile scientific discovery could have been made.