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.

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.

How empty is theory in the presence of fact

How empty is theory in the presence of 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.

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.

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.

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

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

If the facts don't fit the theory, change the facts.

If the facts don't fit the theory, change the facts.