Falsifiability, Popper

In Science, Pseudo-Science and Falsifiability Popper tackles the problem of the strength of a theory. He remarked that the apparent strength of theories which can explain everything was in fact their weakness. The impressive thing about strong theories is the risk involved in their predictions The criterion of the scientitic status of a theory is its falsifiability, or refutability, or testability This places Testing in the middle of this discussion ... 

This, in turn, implies that anyone who advocates the empirical-scientific character of a theory must be able to specify under what conditions [s]he would be prepared to regard it as falsified i.e., [s]he should be able to describe at least some potential falsifiers, and these must, in turn, be falsifiable (Popper, 1989 xxi, xxiii). Hence, if an empiricist uses a universal statement as a basis for the deduction of a singular statement, she must stick to the original meaning (the originally intended use) of the terms used in the singular statement that describes a potential falsifier (Popper, 1979 366-367). 

Such an experiment also fulfills Popper s conclusion on how scientists should work their planned experiments should allow them to falsify a given hypothesis, rather than to verify ( prove ) it. 

It is an essential part of Popper s thesis that any theory which claims to be scientific must be sufficiently precise to be falsifiable. This means that the theory must be able to make... 

When the significance and the reliability of the correspondence between theories and experiments are considered, two main alternatives are available. The Standard View, based on the ideas of logical empiricism, assumes that the experiments can confirm a scientific theory, i.e., that they can increase its probability (here intended as logical confidence in its truth, i.e., in its correspondence with the real world). On the contrary, Falsificationism, first proposed by Karl Popper [17], claims that experiments cannot demonstrate the truth of a theory but can only falsify the theory, i.e., demonstrate that a theory is unfit to describe an experimental result. 

It was mainly the natural sciences that established the new in an unparalleled triumphal procession through history and that pushed it forward again and again, finally accompanied by a justifiably strict scientific theory Do not verify - falsify which Karl Popper claimed in contrast to the positivists. Those who wanted to put forth a hypothesis and wanted to prove it would mostly look for what supported it contradictory findings would gladly be overlooked. Popper elevated the search for error to a principle. Consequently, there were no final truths because the principle was to attempt to disprove each new theory [3]. However, truth was approaching - adaequatio intellectus et rei, which was what Thomas Aquinas called it. 

Scientific models begin as ideas and opinions that are formalized into a language, often, but not necessarily, mathematical language. Furthermore, they must have testable consequences. The emphasis on testability, or falsifiability, is a fundamental attribute (Popper, 1934). 

Unfortunately, it is impossible to design an experiment that will totally disprove a theory based on random phenomena. Various outcomes may occur, some of which may be unlikely but not impossible. Thus Popper s falsifiability condition does not apply. The statistical method advocated by Fisher (1956) attempts to overcome this problem by substituting unlikely for impossible but otherwise follows the principles of the scientific method. With this substitution, Fisher and others proposed conceptual structures for testing theories and scientific hypotheses under conditions of uncertainty that are analogous to the scientific method. However, these approaches, although being very useful in practice, have raised a host of conceptual issues that are the subject of ongoing debates. 

But our purpose here is not an evaluation of Popper s standard of falsifiability of a theory, nor of chemists adherence to that standard. It is rather to contrast the characters of central theories of physics and typical theories of chemistry. We seek to make a comparison between a central theory of physics (e.g., quantum theory as an umbrella notion, with its expression in such formulations as wave mechanics or matrix mechanics) and a body of chemical theory (e.g., transition-state theory, with expression in such formulations as RRKM theory or RRK theory). 

The tenets of Darwinian evolution as applied to enzyme catalysis are thus falsifiable in the Popper sense. The existence of radically different enzyme reaction pathways only in those cases where the uncatalysed pathways are comparably facile is also a telling argument against any sort of intelligent design. 

Some philosophers have wondered about the distinction between science and, say, such areas as astrology and voo doo. Popper came to the conclusion that only scientific theories are falsifiable and therein hes their authenticity. Feyerabend championed the anarchist idea that there is no privileged position for one discipline over the other. My study of relation between physics and chemistry leads to an alternate view. There is a distinction and that stems from the fact that science, based on theory and experiment, discovers the ontological boundaries in nature. Scientists working within... 

All these interpretations fit the experimental results - but which is the most credible This question is, in our opinion, a typical case to be solved on the basis of Popper s book Logic of Scientific Discovery (1935, 1980) A hypothesis is postulated from observations. The hypothesis should then be tested by experiment, designed either to verify or to falsify the original hypothesis. A verification is never definitive and absolute, but a falsification is. If two or more hypotheses fit certain experimental results, a new experiment must be designed in such a way that it will verify one hypothesis, but falsify the other. By such a procedure, erroneous hypotheses can be... 

Karl Popper said it is impossible to confirm a hypothesis. It is only possible to refute it. He rejected the probabilistic approach to medical diagnosis, which today is the most widely accepted model for the diagnostic process. He maintained that probabilistic induction is impossible most of the time because confirmation is impossible. This is not the case in medical practice, where biopsy and surgery can confirm a prior diagnosis. Popper stressed the importance of tests designed to falsify a hypothesis. This applies to the probabilistic approach to the diagnostic process. 

The objective interpretation of probability calculus (Popper, 1976 48, and Appendix IX, Third Comment [1958]) is necessary because no result of statistical sampling is ever inconsistent with a statistical theory unless we make them with the help of. .. rejection rules (Lakatos, 1974 179 see also Nagel, 1971 366). It is under these rejection rules that probability calculus and logical probability approach each other these are also the conditions under which Popper explored the relationship of Fisher s likelihood function to his degree of corroboration, and the conditions arise only if the random sample is large and (e) is a statistical report asserting a good fit (Farris et ah, 2001). In addition to the above, in order to maintain an objective interpretation of probability calculus, Popper also required that once the specified conditions are obtained, we must proceed to submit (e) itself to a critical test, that is, try to find observable states of affairs that falsify (e). 

So in practice, there can be no talk of a precise, unequivocal falsification of any theory. However, says Popper (1979 391), it is not in his interest to deal with the problem of science in such a practical, naturalistic perspective. Popper considered his own theory of falsifiability, and of scientific method in general, as methodological or philosophical, not as empirical and hence not as falsifiable in itself (analogous to the verificationists conundrum that the principle of verification is not itself verifiable) to consider the scientific method as empirical is to adopt a naturalistic perspective (Popper, 1974a 1010). Although it is possible to study science from a purely descriptive perspective, recording all the facts, difficulties and failures. 

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