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.

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.

[Do not] put too much confidence in experimental results until they have been confirmed by theory.

[Do not] put too much confidence in experimental results until they have been confirmed by theory.

Many things difficult to design prove easy to performance.

Many things difficult to design prove easy to performance.

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.

A young boy is a theory, an old man is a fact.

A young boy is a theory, an old man is a fact.

How empty is theory in the presence of fact

How empty is theory in the presence of fact

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

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

Whenever a theory appears to you as the only possible one, take this as a sign that you have neither read more

Whenever a theory appears to you as the only possible one, take this as a sign that you have neither understood the theory nor the problem which it was intended to solve