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.

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.

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.

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

In theory there is no difference between theory and practice. In practice there is.

In theory there is no difference between theory and practice. In practice there is.

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.

An ounce of action is worth a ton of theory.

An ounce of action is worth a ton of theory.

It is the theory that decides what can be observed

It is the theory that decides what can be observed