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.

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

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

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.

[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.

There is a theory which states that if ever for any reason anyone discovers what exactly the Universe is for read more

There is a theory which states that if ever for any reason anyone discovers what exactly the Universe is for and why it is here it will instantly disappear and be replaced by something even more bizarre and inexplicable. There is another that states that this has already happened.

An ounce of action is worth a ton of theory.

An ounce of action is worth a ton of 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

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.