We are left with the indisputable but irritating conclusion: 0 = 0. This is a favourite device that mathematical equations resort to, when we propound stupid questions.

Science aims at constructing a world which shall be symbolic of the world of commonplace experience. It is not at all necessary that every individual symbol that is used should represent something in common experience or even something explicable in terms of common experience.

Not only is the universe stranger than we imagine, it is stranger than we can imagine.

It was the experience of mystery - even if mixed with fear - that engendered religion.

Cogito cogito ergo cogito sum (I think that I think, therefore I think that I am.)

If someone points out to you that your pet theory of the universe is in disagreement with Maxwell's equations – then so much the worse for Maxwell's equations. If it is found to be contradicted by observation – well, these experimentalists do bungle things sometimes. But if your theory is found to be against the second law of thermodynamics I can give you no hope; there is nothing for it but to collapse in deepest humiliation.

To a request to explain what an electron is really supposed to be we can only answer, 'It is part of the A B C of physics.'

The most insignificant present has over the most significant past the advantage of reality.

Scientists were rated as great heretics by the church, but they were truly religious men because of their faith in the orderliness of the universe.

There is nothing new under the sun but there are lots of old things we don't know.