Ludwig von Mises Quotes

Theory and fact are equally strong and utterly interdependent; one has no meaning without the other. We need theory to organize and interpret facts, even to know what we can or might observe. And we need facts to validate theories and give them substance.

It is a very long and very difficult road from a fact to a conclusion. But it is a million times longer from a theory to a fact.

Facts and theories are different things, not rungs in a hierarchy of increasing certainty. Facts are the world's data. Theories are structures of ideas that explain and interpret facts. Facts do not go away while scientists debate rival theories for explaining them. Einstein's theory of gravitation replaced Newton's, but apples did not suspend themselves in mid-air pending the outcome.

It is that of increasing knowledge of empirical fact, intimately combined with changing interpretations of this body of fact - hence changing general statements about it - and, not least, a changing a structure of the theoretical system.

Facts do not speak for themselves. They speak for or against competing theories. Facts divorced from theories or visions are mere isolated curiosities.

In degenerating programmes, however, theories are fabricated only in order to accommodate known facts

Without a theory the facts are silent.

Science is the most complete presentment of facts with the least expenditure of thought

The theory must not contradict empirical facts.

Theories without facts may be barren, but facts without theories are meaningless.

For every fact there is an infinity of hypotheses.

Observations always involve theory.

Evidence is fact that discriminates between one theory and another. Facts do not speak for themselves. They speak for or against competing theories. Theories can be devastated by facts but they can never be proven correct by facts. What empirical verification can do is to reveal which of the competing theories currently being considered is more consistent with that which is known factually. Some other theory may come along tomorrow that is still more consistent with the facts, or explains those facts with fewer, clearer, or more manageable assumptions.

The scientific method actually correctly uses the most direct evidence as the most reliable, because that's the way you are least likely to get led astray into dead ends and to misunderstand your data.

No matter how beautiful the theory, one irritating fact can dismiss the entire formulism, so it has to be proven.

To me, what makes physics physics is that experiment is intimately connected to theory. It's one whole.

A science is something which is constructed from truth on workable axioms. There are 55 axioms in scientology which are very demonstrably true, and on these can be constructed a great deal.

It is not observation but theory that led me to this result that experience has confirmed afterwards.

To say that prediction is the purpose of a scientific theory is to confuse means with ends. It is like saying that the purpose of a spaceship is to burn fuel. ... Passing experimental tests is only one of many things a theory has to do to achieve the real purpose of science, which is to explain the world.

A theory can be proved by experiment; but no path leads from experiment to the birth of a theory.

Physics is a good framework for thinking. ... Boil things down to their fundamental truths and reason up from there.

Observation and theory get on best when they are mixed together, both helping one another in the pursuit of truth. It is a good rule not to put overmuch confidence in a theory until it has been confirmed by observation. I hope I shall not shock the experimental physicists too much if I add that it is also a good rule not to put overmuch confidence in the observational results that are put forward until they have been confirmed by theory.

Science walks forward on two feet, namely theory and experiment.

When the fact doesn't meet the theory then let go the theory.

Science walks forward on two feet, namely theory and experiment. Sometimes it is one foot which is put forward first, sometimes the other, but continuous progress is only made by the use of both.