We haven't got the money, so we've got to think.

Gentlemen, we have run out of money. It is time to start thinking.

All of physics is either impossible or trivial. It is impossible until you understand it, and then it becomes trivial.

A good scientific theory should be explicable to a barmaid.

That which is not measurable is not science. That which is not physics is stamp collecting.

The great object is to find the theory of the matter [of X-rays] before anyone else, for nearly every professor in Europe is now on the warpath.

Splitting the atom is like trying to shoot a gnat in the Albert Hall at night and using ten million rounds of ammunition on the off chance of getting it. That should convince you that the atom will always be a sink of energy and never a reservoir of energy.