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.

Conjecture as to things useful, is good; but conjecture as to what it would be useless to know, is very read more

Conjecture as to things useful, is good; but conjecture as to what it would be useless to know, is very idle.

Life is so unlike theory.

Life is so unlike theory.

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

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

In scientific work, those who refuse to go beyond fact rarely get as far as fact.

In scientific work, those who refuse to go beyond fact rarely get as far as fact.

Relativity applies to physics, not ethics

Relativity applies to physics, not ethics

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.

Many things difficult to design prove easy to performance.

Many things difficult to design prove easy to performance.

You have to know you can first. How comes later.

You have to know you can first. How comes later.