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.

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.

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.

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.

How empty is theory in the presence of fact

How empty is theory in the presence of fact

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

Many things difficult to design prove easy to performance.

Many things difficult to design prove easy to performance.

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.