Asked in 1919 whether it was true that only three people in the world understood the theory of general relativity, [Eddington] allegedly replied: "Who's the third?"

It is impossible to trap modern physics into predicting anything with perfect determinism because it deals with probabilities from the outset.

Observation and theory get on best when they are mixed together, both helping one another in the pursuit of truth. It is a good rule not to put overmuch confidence in a theory until it has been confirmed by observation. I hope I shall not shock the experimental physicists too much if I add that it is also a good rule not to put overmuch confidence in the observational results that are put forward until they have been confirmed by theory.

There is no space without aether, and no aether which does not occupy space.

The idea of a universal mind or Logos would be, I think, a fairly plausible inference from the present state of scientific theory.

It is reasonable to hope that in the not too distant future we shall be competent to understand so simple a thing as a star.

Every body continues in its state of rest or uniform motion in a straight line, except insofar as it doesn't.