Language analysts believe that there are no genuine philosophical problems, or that the problems of philosophy, if any, are problems of linguistic usage, or of the meaning of words. I, however, believe that there is at least one philosophical problem in which all thinking men are interested. It is the problem of cosmology: the problem of understanding the world—including ourselves, and our knowledge, as part of the world. All science is cosmology, I believe, and for me the interest of philosophy, no less than of science, lies solely in the contributions which it has made to it. (查看原文)
Language analysts regard themselves as practitioners of a method peculiar to philosophy. I think they are wrong, for I believe in the following thesis.
Philosophers are as free as others to use any method in searching for truth. There is no method peculiar to philosophy.
A second thesis which I should like to propound here is this. The central problem of epistemology has always been and still is the problem of the growth of knowledge. And the growth of knowledge can be studied best by studying the growth of scientific knowledge.
I do not think that the study of the growth of knowledge can be replaced by the study of linguistic usages, or of language systems. (查看原文)
The point is that, whenever we propose a solution to a problem, we ought to try as hard as we can to overthrow our solution, rather than defend it. (查看原文)
In this formulation we see that natural laws might be compared to ‘proscriptions’ or ‘prohibitions’. They do not assert that something exists or is the case; they deny it. They insist on the non-existence of certain things or states of affairs, proscribing or prohibiting, as it were, these things or states of affairs: they rule them out. And it is precisely because they do this that they are falsifiable. If we accept as true one singular statement which, as it were, infringes the prohibition by asserting the existence of a thing (or the occurrence of an event) ruled out by the law, then the law is refuted. (An instance would be, ‘In such-and-such a place, there is an apparatus which is a perpetual motion machine’.)
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Strictly existential statements, by contrast, cannot be falsified. No si... (查看原文)
This is the reason why strictly existential statements are not falsifiable. We cannot search the whole world in order to establish that something does not exist, has never existed, and will never exist. It is for precisely the same reason that strictly universal statements are not verifiable. Again, we cannot search the whole world in order to make sure that nothing exists which the law forbids. Nevertheless, both kinds of strict statements, strictly existential and strictly universal, are in principle empirically decidable; each, however, in one way only: they are unilaterally decidable. Whenever it is found that something exists here or there, a strictly existential statement may thereby be verified, or a universal one falsified. (查看原文)
Now it is far from obvious, from a logical point of view, that we are justified in inferring universal statements from singular ones, no matter how numerous; for any conclusion drawn in this way may always turn out to be false: no matter how many instances of white swans we may have observed, this does not justify the conclusion that all swans are white. (查看原文)
But I shall certainly admit a system as empirical or scientific only if it is capable of being tested by experience. These considerations suggest that not the verifiability but the falsifiability of a system is to be taken as a criterion of demarcation. In other words: I shall not require of a scientific system that it shall be capable of being singled out, once and for all, in a positive sense; but I shall require that its logical form shall be such that it can be singled out, by means of empirical tests, in a negative sense: it must be possible for an empirical scientific system to be refuted by experience. (查看原文)
Now I hold that scientific theories are never fully justifiable or verifiable, but that they are nevertheless testable. I shall therefore say that the objectivity of scientific statements lies in the fact that they can be inter-subjectively tested. (查看原文)
Basic statements are therefore - in the material mode of speech - statements asserting that an observable event is occurring in a certain individual region of space and time. (查看原文)
But we do not attempt to justify basic statements by these experiences. Experiences can motivate a decision, and hence an acceptance or a rejection of a statement, but a basic statement cannot be justified by them—no more than by thumping the table. (查看原文)
It may now be possible for us to answer the question: How and why do we accept one theory in preference to others?
The preference is certainly not due to anything like a experiential justification of the statements composing the theory; it is not due to a logical reduction of the theory to experience. We choose the theory which best holds its own in competition with other theories; the one which, by natural selection, proves itself the fittest to survive. This will be the one which not only has hitherto stood up to the severest tests, but the one which is also testable in the most rigorous way. A theory is a tool which we test by applying it, and which we judge as to its fitness by the results of its applications.
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For the conventionalist, the acceptance of universal statements is gov... (查看原文)
Simple statements, if knowledge is our object, are to be prized more highly than less simple ones because they tell us more; because their empirical content is greater; and because they are better testable. (查看原文)
But since the conventionalist does not treat his theories as falsifiable systems but rather as conventional stipulations, he obviously means by ‘simplicity’ something different from degree of falsifiability. (查看原文)
This state of affairs is connected with the so-called uncertainty principle enunciated by Heisenberg. It may, perhaps, be explained as follows. Every physical measurement involves an exchange of energy between the object measured and the measuring apparatus (which might be the observer himself). A ray of light, for example, might be directed upon the object, and part of the dispersed light reflected by the object might be absorbed by the measuring apparatus. Any such exchange of energy will alter the state of the object which, after being measured, will be in a state different from before. Thus the measurement yields, as it were, knowledge of a state which has just been destroyed by the measuring process itself. This interference by the measuring process with the object measured can be neg... (查看原文)
Science is not a system of certain, or well-established, statements; nor is it a system which steadily advances towards a state of finality. Our science is not knowledge (episteme): it can never claim to have attained truth, or even a substitute for it, such as probability.
Yet science has more than mere biological survival value. It is not only a useful instrument. Although it can attain neither truth nor probability, the striving for knowledge and the search for truth are still the strongest motives of scientific discovery.
We do not know: we can only guess. And our guesses are guided by the unscientific, the metaphysical (though biologically explicable) faith in laws, in regularities which we can uncover—discover. Like Bacon, we might describe our own contemporary science—‘the metho... (查看原文)
It is we who always formulate the questions to be put to nature; it is we who try again and again to put these question so as to elicit a clear-cut ‘yes’ or ‘no’ (for nature does not give an answer unless pressed for it). And in the end, it is again we who give the answer; it is we ourselves who, after severe scrutiny, decide upon the answer to the question which we put to nature—after protracted and earnest attempts to elicit from her an unequivocal ‘no’.
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The old scientific ideal of episteme—of absolutely certain, demonstrable knowledge—has proved to be an idol. The demand for scientific objectivity makes it inevitable that every scientific statement must remain tentative for ever. It may indeed be corroborated, but every corroboration is relative to other statements which, again, are... (查看原文)
The wrong view of science betrays itself in the craving to be right; for it is not his possession of knowledge, of irrefutable truth, that makes the man of science, but his persistent and recklessly critical quest for truth.
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Science never pursues the illusory aim of making its answers final, or even probable. Its advance is, rather, towards an infinite yet attainable aim: that of ever discovering new, deeper, and more general problems, and of subjecting our ever tentative answers to ever renewed and ever more rigorous tests. (查看原文)
For although probability statements play such a vitally important role in empirical science, they turn out to be in principle impervious to strict falsification. Yet this very stumbling block will become a touchstone upon which to test my theory, in order to find out what it is worth. (查看原文)
People with inductivist leanings may tend to overlook the hypothetical character of these estimates: they may confuse a hypothetical estimate, i.e. a frequency-prediction based on statistical extrapolation, with one of its empirical ‘sources’—the classifying and actual counting of past occurrences and sequences of occurrences. The claim is often made that we ‘derive’ estimates of probabilities—that is, predictions of frequencies—from past occurrences which have been classified and counted (such as mortality statistics). But from a logical point of view there is no justification for this claim. We have made no logical derivation at all. What we may have done is to advance a non-verifiable hypothesis which nothing can ever justify logically: the conjecture that frequencies will remain consta... (查看原文)
