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.

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

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

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.

A young boy is a theory, an old man is a fact.

A young boy is a theory, an old man is a 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.

An ounce of action is worth a ton of theory.

An ounce of action is worth a ton of theory.

[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.

Our theories of the eternal are as valuable as are those which a chick which has not broken its way read more

Our theories of the eternal are as valuable as are those which a chick which has not broken its way through its shell might form of the outside world.

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.