An ounce of action is worth a ton of theory.

An ounce of action is worth a ton of 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.

Let us work without theorizing, 'Tis the only way to make life endurable.

Let us work without theorizing, 'Tis the only way to make life endurable.

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.

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 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.

How empty is theory in the presence of fact

How empty is theory in the presence of fact

Relativity applies to physics, not ethics

Relativity applies to physics, not ethics