Richard P. Feynman Quotes

A single test which proves some piece of theory wrong is more valuable than a hundred tests showing that idea might be true.

If it disagrees with experiment, it's wrong.

The true contrast between science and myth is more nearly touched when we say that science alone is capable of verification.

Science doesn't work by voting. Did people vote on the theory of relativity? No! It's either right or it's wrong. Do we vote on whether genetics is a good theory or not? Of course not.

The ultimate arbiter of truth is experiment, not the comfort one derives from one's a priori beliefs, nor the beauty or elegance one ascribes to one's theoretical models.

There are many examples of old, incorrect theories that stubbornly persisted, sustained only by the prestige of foolish but well-connected scientists... Many of these theories have been killed off only when some decisive experiment exposed their incorrectness... Thus the yeoman work in any science, and especially physics, is done by the experimentalist, who must keep the theoreticians honest.

There never comes a point where a theory can be said to be true. The most that one can claim for any theory is that it has shared the successes of all its rivals and that it has passed at least one test which they have failed.

The scientists from Franklin to Morse were clear thinkers and did not produce erroneous theories. The scientists of today think deeply instead of clearly. One must be sane to think clearly, but one can think deeply and be quite insane. Today's scientists have substituted mathematics for experiments, and they wander off through equation after equation, and eventually build a structure which has no relation to reality.

In physics, opinions don't matter, only demonstrated experiments. The day the fellow succeeds, if ever, he won't need anybody else's opinion.

The test of all knowledge is experiment. Experiment is the sole judge of scientific truth.

Science is organized common sense where many a beautiful theory was killed by an ugly fact.

It is an acknowledged truth in philosophy that a just theory will always be confirmed by experiment.

One of the distinguishing features of anything that aspires to the name of science is the reproducibility of experimental results.

If the experiments which I urge be defective, it cannot be difficult to show the defects; but if valid, then by proving the theory, they must render all objections invalid.

True science is never speculative; it employs hypotheses as suggesting points for inquiry, but it never adopts the hypotheses as though they were demonstrated propositions.

There is no justifiable prediction about how the hypothesis will hold up in the future; its degree of corroboration simply is a historical statement describing how severely the hypothesis has been tested in the past.

We are certainly not to relinquish the evidence of experiments for the sake of dreams and vain fictions of our own devising; nor are we to recede from the analogy of Nature, which is wont to be simple and always consonant to itself.

You make observations, write theories to fit them, try experiments to disprove the theories and, if you can't, you've got something.

I am not here concerned with intent, but with scientific standards, especially the ability to tell the difference between a fact, an opinion, a hypothesis, and a hole in the ground.

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.

Science is true, whether you believe it or not.

Here is an entirely banal idea that I think has the potential to change the world: Take evidence seriously. Taking evidence seriously does not mean privileging numbers over all other forms of knowledge - theories, narratives, images. Nor does it mean the kind of radical skepticism that questions everything to the point where no action is possible.

In science consensus is irrelevant. What is relevant is reproducible results.

Science is a mechanism, a way of trying to improve your knowledge of nature. It's a system for testing your thoughts against the universe, and seeing whether they match.

We must conduct research and then accept the results. If they don't stand up to experimentation, Buddha's own words must be rejected.