Richard P. Feynman Quotes

First you guess. Don't laugh, this is the most important step. Then you compute the consequences. Compare the consequences to experience. If it disagrees with experience, the guess is wrong. In that simple statement is the key to science. It doesn't matter how beautiful your guess is or how smart you are or what your name is. If it disagrees with experience, it's wrong. That's all there is to it.

If it disagrees with experiment, it's wrong.

Science doesn't purvey absolute truth. Science is a mechanism... for testing your thoughts against the universe.

Science has been effective at furthering our understanding of nature because the scientific ethos is based on three key principles: (1) follow the evidence wherever it leads; (2) if one has a theory, one needs to be willing to try to prove it wrong as much as one tries to prove that it is right; (3) 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.

The work of science has nothing whatever to do with consensus. Consensus is the business of politics. Science, on the contrary, requires only one investigator who happens to be right, which means that he or she has results that are verifiable by reference to the real world. In science consensus is irrelevant. What is relevant is reproducible results. The greatest scientists in history are great precisely because they broke with the consensus.

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

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

Science isn't done by consensus. It's done by rigorous testing.

Science is the acceptance of what works and the rejection of what does not. That needs more courage than we might think.

Imagination should give wings to our thoughts but we always need decisive experimental proof, and when the moment comes to draw conclusions and to interpret the gathered observations, imagination must be checked and documented by the factual results of the experiment.

Experiments are mediators between nature and idea.

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.

Scientists actively approach the door to knowledge—the boundary of the domain of what we know. We question and explore and we change our views when facts and logic force us to do so. We are confident only in what we can verify through experiments or in what we can deduce from experimentally confirmed hypotheses.

Any work of science, no matter what its point of departure, cannot become fully convincing until it crosses the boundary between the theoretical and the experimental: Experimentation must give way to argument, and argument must have recourse to experimentation.

Science replaces private prejudice with public, verifiable evidence.

Experimental evidence is the final arbiter of right and wrong.

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.

The scientific tradition is distinguished from the pre-scientific tradition by having two layers. Like the latter, it passes on its theories; but it also passes on a critical attitude towards them.

If the evidence says you're wrong, you don't have the right theory. You change the theory, not the evidence.

The office of science is not to record possibilities; but to ascertain what nature does ... As far as Darwinism deals with mere arguments of possibilities or even probabilities, without a basis of fact, it departs from the true scientific method and injures science, as most of the devotees of the new ism have already done.

I'm not a religious man... I find I am a fan of science. I believe in science. A humility before the facts. I find that a moving and beautiful thing. And belief in the unknown I find less interesting. I find the known and the knowable interesting enough.

We have to learn again that science without contact with experiments is an enterprise which is likely to go completely astray into imaginary conjecture.

If you're a physicist, for heaven's sake, and here is the experiment, and you have a theory, and the theory doesn't agree with the experiment, then you have to cut out the theory. You were wrong with the theory.

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.