I never once made a discovery ... I speak without exaggeration that I have constructed three thousand different theories in read more

I never once made a discovery ... I speak without exaggeration that I have constructed three thousand different theories in connection with the electric light ... Yet in only two cases did my experiments prove the truth of my theory.

You cannot run a business, or anything else, on a theory.

You cannot run a business, or anything else, on a theory.

There can be no theory of any account unless it corroborate with the theory of the earth.

There can be no theory of any account unless it corroborate with the theory of the earth.

There is a theory which states that if ever for any reason anyone discovers what exactly the Universe is for read more

There is a theory which states that if ever for any reason anyone discovers what exactly the Universe is for and why it is here it will instantly disappear and be replaced by something even more bizarre and inexplicable. There is another that states that this has already happened.

It is the theory that decides what can be observed

It is the theory that decides what can be observed

How empty is theory in the presence of fact

How empty is theory in the presence of fact

A theory is no more like a fact than a photograph is like a person.

A theory is no more like a fact than a photograph is like a person.

The theory seems to be that as long as a man is a failure he is one of God's children, read more

The theory seems to be that as long as a man is a failure he is one of God's children, but that as soon as he succeeds he is taken over by the Devil.

A theory has only the alternative of being right or wrong. A model has a third possibility - it may read more

A theory has only the alternative of being right or wrong. A model has a third possibility - it may be right but irrelevant.