He who loves practice without theory is like the sailor who boards ship without a rudder and compass and never read more

He who loves practice without theory is like the sailor who boards ship without a rudder and compass and never knows where he may cast.

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.

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

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

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

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

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

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

Many things difficult to design prove easy to performance.

Many things difficult to design prove easy to performance.

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.

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.