Rudolf Carnap Quotes

The truth of a theory can never be proven, for one never knows if future experience will contradict its conclusions.

I hold that the propositions embodied in natural science are not derived by any definite rule from the data of experience, and that they can neither be verified nor falsified by experience according to any definite rule.

A valid scientific theory is predictive, verifiable, and replicable. To me, that's beautiful.

There is no more common error than to assume that, because prolonged and accurate mathematical calculations have been made, the application of the result to some fact of nature is absolutely certain.

Any physical theory is always provisional, in the sense that it is only a hypothesis: you can never prove it. No matter how many times the results of experiments agree with some theory, you can never be sure that the next time the result will not contradict the theory.

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

Science, in its ultimate ideal, consists of a set of propositions arranged in a hierarchy, the lowest level of the hierarchy being concerned with particular facts, and the highest with some general law, governing everything in the universe. The various levels in the hierarchy have a two-fold logical connection, travelling one up, one down; the upward connection proceeds by induction, the downward by deduction.

The scientist believes in proof without certainty.

It does not make any difference how beautiful your guess is. It does not make any difference how smart you are, who made the guess, or what his name is if it disagrees with experiment it is wrong. That is all there is to it.

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.

With no specific procedure, man arrived at sweeping conclusions about the universe that have proven to be true.

The theory must not contradict empirical facts.

We must have the real thing before we can have a science of a thing.

Science, at bottom, is really anti-intellectual. It always distrusts pure reason, and demands the production of objective fact.

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.

As in the experimental sciences, truth cannot be distinguished from error as long as firm principles have not been established through the rigorous observation of facts.

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.

The logic of science was infallible, and if the scientists were sometimes mistaken, this was assumed to be only from their mistaking its rules.

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.

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.

If it disagrees with experiment, it's wrong.

Science sometimes improves hypotheses and sometimes disproves them. But proof would be another matter and perhaps never occurs except in the realms of totally abstract tautology. We can sometimes say that if such and such abstract suppositions or postulates are given, then such and such abstract suppositions or postulates are given, then such and such must follow absolutely. But the truth about what can be perceived or arrived at by induction from perception is something else again.

In nature, when you conduct science, it is the natural world that is the ultimate decider in what is true and what is not.