Editing Karl Popper (section)

== Criticism ==
Most criticisms of Popper's philosophy are [[Falsifiability#Controversies|of the falsification]], or error elimination, element in his account of problem solving. Popper presents falsifiability as both an ideal and as an important principle in a practical method of effective human problem solving; as such, the current conclusions of science are stronger than pseudo-sciences or [[non-science]]s, insofar as they have survived this particularly vigorous selection method.<ref>{{Cite journal |last=Derksen |first=Maarten |date=2019-08-01 |title=Putting Popper to work |journal=Theory & Psychology |language=en |volume=29 |issue=4 |pages=449–465 |doi=10.1177/0959354319838343 |issn=0959-3543 |doi-access=free}}</ref>

He does not argue that any such conclusions are therefore true, or that this describes the actual methods of any particular scientist. Rather, it is recommended as an essential principle of methodology that, if enacted by a system or community, will lead to slow but steady progress of a sort (relative to how well the system or community enacts the method). It has been suggested that Popper's ideas are often mistaken for a hard logical account of truth because of the historical co-incidence of their appearing at the same time as [[logical positivism]], the followers of which mistook his aims for their own.<ref>Bryan Magee 1973: Popper (Modern Masters series)</ref>

The [[confirmation holism|Quine–Duhem thesis]] argues that it is impossible to test a single hypothesis on its own, since each one comes as part of an environment of theories. Thus we can only say that the whole package of relevant theories has been collectively [[Falsifiability|falsified]], but cannot conclusively say which element of the package must be replaced. An example of this is given by the discovery of the planet [[Neptune]]: when the motion of [[Uranus]] was found not to match the predictions of [[Newton's laws]], the theory "There are seven planets in the solar system" was rejected, and not Newton's laws themselves. Popper discussed this critique of [[naive falsificationism]] in Chapters 3 and 4 of ''[[The Logic of Scientific Discovery]]''.

The philosopher [[Thomas Kuhn]] writes in ''[[The Structure of Scientific Revolutions]]'' (1962) that he places an emphasis on anomalous experiences similar to that which Popper places on falsification. However, he adds that anomalous experiences cannot be identified with falsification, and questions whether theories could be falsified in the manner suggested by Popper.<ref>{{Cite book |last=Kuhn |first=Thomas |title=The Structure of Scientific Revolutions. 50th Anniversary Edition |publisher=University of Chicago Press |year=2012 |location=Chicago and London |pages=145–146}}</ref> Kuhn argues in ''The Essential Tension'' (1977) that while Popper was correct that [[psychoanalysis]] cannot be considered a science, there are better reasons for drawing that conclusion than those Popper provided.<ref>{{Cite book |last=Kuhn |first=Thomas S. |url=https://archive.org/details/essentialtension0000kuhn |title=The Essential Tension: Studies in Scientific Tradition and Change |publisher=University of Chicago Press |year=1977 |isbn=978-0-226-45805-2 |location=Chicago |page=[https://archive.org/details/essentialtension0000kuhn/page/274 274] |url-access=registration}}</ref> Popper's student [[Imre Lakatos]] attempted to reconcile Kuhn's work with [[Critical rationalism|falsificationism]] by arguing that science progresses by the falsification of ''research programs'' rather than the more specific [[universal quantification|universal statements]] of naive falsificationism.<ref>{{Cite web |last1=Musgrave |first1=Alan |last2=Pigden |first2=Charles |editor-last=Zalta |editor-first=Edward N |editor2-last=Nodelman |editor2-first=Uri |title=Imre Lakatos |url=https://plato.stanford.edu/entries/lakatos/#FalsMethScieReseProg1970 |access-date=2023-03-12 |website=The Stanford Encyclopedia of Philosophy |publisher=Metaphysics Research Lab, Stanford University |quote="Lakatos's methodology has been seen, rightly, as an attempt to reconcile Popper's falsificationism with the views of Thomas Kuhn." |edition=Spring 2023}}</ref>

Popper claimed to have recognised already in the 1934 version of his ''Logic of Discovery'' a fact later stressed by Kuhn, "that scientists necessarily develop their ideas within a definite theoretical framework", and to that extent to have anticipated Kuhn's central point about "normal science".<ref>K R Popper (1970), "Normal Science and its Dangers", pp. 51–58 in [[#refcgk1970|I Lakatos & A Musgrave (eds.) (1970)]], at [https://books.google.com/books?id=Vutfm5n6LKYC&pg=PA51 p. 51].</ref> However, Popper criticised what he saw as Kuhn's relativism, this criticism being at the heart of the [[Kuhn-Popper debate]].<ref>K R Popper (1970), in I Lakatos & A Musgrave (eds.) (1970), at [https://books.google.com/books?id=Vutfm5n6LKYC&pg=PA56 p. 56].</ref> Also, in his collection ''Conjectures and Refutations: The Growth of Scientific Knowledge'' (Harper & Row, 1963), Popper writes,
{{blockquote|Science must begin with myths, and with the criticism of myths; neither with the collection of observations, nor with the invention of experiments, but with the critical discussion of myths, and of magical techniques and practices. The scientific tradition is distinguished from the pre-scientific tradition in having two layers. Like the latter, it passes on its theories; but it also passes on a critical attitude towards them. The theories are passed on, not as dogmas, but rather with the challenge to discuss them and improve upon them.}}

Another objection is that it is not always possible to demonstrate falsehood definitively, especially if one is using [[statistical significance|statistical]] criteria to evaluate a [[null hypothesis]]. More generally it is not always clear, if evidence contradicts a hypothesis, that this is a sign of flaws in the hypothesis rather than of flaws in the evidence. However, this is a misunderstanding of what Popper's philosophy of science sets out to do. Rather than offering a set of instructions that merely need to be followed diligently to achieve science, Popper makes it clear in ''The Logic of Scientific Discovery'' that his belief is that the resolution of conflicts between hypotheses and observations can only be a matter of the collective judgment of scientists, in each individual case.<ref name="LdF">Popper, Karl, (1934) ''Logik der Forschung'', Springer. Vienna. Amplified English edition, Popper (1959), {{ISBN|0415278449}}</ref>

In ''Science Versus Crime'', Houck writes<ref>Houck, Max M., ''Science Versus Crime'', Infobase Publishing, 2009, [https://books.google.com/books?id=z4UFw18Lwy0C p. 65]</ref> that Popper's falsificationism can be questioned logically: it is not clear how Popper would deal with a statement like "for every metal, there is a temperature at which it will melt". The hypothesis cannot be falsified by any possible observation, for there will always be a higher temperature than tested at which the metal may in fact melt, yet it seems to be a valid scientific hypothesis. These examples were pointed out by [[Carl Gustav Hempel]]. Hempel came to acknowledge that logical positivism's verificationism was untenable, but argued that falsificationism was equally untenable on logical grounds alone. The simplest response to this is that, because Popper describes how theories attain, maintain and lose scientific status, individual consequences of currently accepted scientific theories are scientific in the sense of being part of tentative scientific knowledge, and both of Hempel's examples fall under this category. For instance, [[atomic theory]] implies that all metals melt at some temperature.

An early adversary of Popper's critical rationalism, [[Karl-Otto Apel]] attempted a comprehensive refutation of Popper's philosophy. In ''Transformation der Philosophie'' (1973), Apel charged Popper with being guilty of, amongst other things, a pragmatic contradiction.<ref>See: "Apel, Karl-Otto," ''La philosophie de A a Z'', by Elizabeth Clement, Chantal Demonque, Laurence Hansen-Love, and Pierre Kahn, Paris, 1994, Hatier, 19–20. See Also: ''Towards a Transformation of Philosophy (Marquette Studies in Philosophy, No 20)'', by Karl-Otto Apel, trans., Glyn Adey and David Fisby, Milwaukee, 1998, Marquette University Press.</ref>

The philosopher [[Adolf Grünbaum]] argues in ''[[The Foundations of Psychoanalysis]]'' (1984) that Popper's view that psychoanalytic theories, even in principle, cannot be falsified is incorrect.<ref>{{Cite book |last=Grünbaum |first=Adolf |url=https://archive.org/details/foundationsofpsy00grun |title=The Foundations of Psychoanalysis: A Philosophical Critique |publisher=University of California Press |year=1984 |location=Berkeley |pages=[https://archive.org/details/foundationsofpsy00grun/page/103 103]–112 |url-access=registration}}</ref> The philosopher [[Roger Scruton]] argues in ''[[Sexual Desire (book)|Sexual Desire]]'' (1986) that Popper was mistaken to claim that Freudian theory implies no testable observation and therefore does not have genuine predictive power. Scruton maintains that Freudian theory has both "theoretical terms" and "empirical content". He points to the example of Freud's theory of [[Repression (psychology)|repression]], which in his view has "strong empirical content" and implies testable consequences. Nevertheless, Scruton also concluded that Freudian theory is not genuinely scientific.<ref>{{Cite book |last=Scruton |first=Roger |title=Sexual Desire: A Philosophical Investigation |publisher=Phoenix |year=1994 |location=London |page=201 |author-link=Roger Scruton}}</ref> The philosopher [[Charles Taylor (philosopher)|Charles Taylor]] accuses Popper of exploiting his worldwide fame as an [[epistemologist]] to diminish the importance of philosophers of the 20th-century [[continental philosophy|continental tradition]]. According to Taylor, Popper's criticisms are completely baseless, but they are received with an attention and respect that Popper's "intrinsic worth hardly merits".<ref>Taylor, Charles, "Overcoming Epistemology", in ''Philosophical Arguments'', Harvard University Press, 1995, {{ISBN|0674664779}}</ref>

The philosopher [[John Gray (philosopher)|John Gray]] argues that Popper's account of scientific method would have prevented the theories of [[Charles Darwin]] and [[Albert Einstein]] from being accepted.<ref>{{Cite book |last=Gray |first=John |url=https://archive.org/details/strawdogsthought00gray |title=Straw Dogs |publisher=Granta Books, London |year=2002 |isbn=978-1-86207-512-2 |page=[https://archive.org/details/strawdogsthought00gray/page/n19 22] |url-access=limited}}</ref> However, Gray's criticism with regards to Einstein is at odds with the fact that Popper frequently used Einstein's theory of general relativity as a case study of how the principle of falsifiability works in practice.<ref>'Conjectures and refutations', Karl Popper, Routledge, p.47: "Einstein's gravitational theory had let to the result that light must be attracted by heavy bodies (such as the sun)...Now the impressive thing about this case is the risk involved in a prediction of this kind. If observation shows that the predicted effect is definitely absent, then the theory is simply refuted. The theory is ''incompatible with certain possible results of observation''-in fact with results which everybody before Einstein would have expected." Popper separately recounts (p.44) how as a student "We...were thrilled with the result of Eddington's eclipse observations which in 1919 brought the first important confirmation of Einstein's theory of gravitation."</ref>

The philosopher and psychologist Michel ter Hark writes in ''Popper, Otto Selz and the Rise of Evolutionary Epistemology'' (2004) that Popper took some of his ideas from his tutor, the German psychologist [[Otto Selz]]. Selz never published his ideas, partly because of the rise of [[Nazism]], which forced him to quit his work in 1933 and prohibited any reference to his ideas. Popper, the historian of ideas and his scholarship, is criticised in some academic quarters for his treatment of Plato and Hegel.<ref>Wild, John (1964). ''Plato's Modern Enemies and the Theory of Natural Law''. Chicago: University of Chicago Press. p. 23. "Popper is committing a serious historical error in attributing the organic theory of the state to Plato and accusing him of all the fallacies of post-Hegelian and Marxist historicism—the theory that history is controlled by the inexorable laws governing the behavior of superindividual social entities of which human beings and their free choices are merely subordinate manifestations."</ref><ref>Levinson, Ronald B. (1970). ''In Defense of Plato''. New York: Russell and Russell. p. 20. "In spite of the high rating one must accord his initial intention of fairness, his hatred for the enemies of the 'open society,' his zeal to destroy whatever seems to him destructive of the welfare of mankind, has led him into the extensive use of what may be called terminological counterpropaganda. ... With a few exceptions in Popper's favor, however, it is noticeable that reviewers possessed of special competence in particular fields—and here Lindsay is again to be included—have objected to Popper's conclusions in those very fields. ... "Social scientists and social philosophers have deplored his radical denial of historical causation, together with his espousal of Hayek's systematic distrust of larger programs of social reform; historical students of philosophy have protested his violent polemical handling of Plato, Aristotle, and particularly Hegel; ethicists have found contradictions in the ethical theory ('critical dualism') upon which his polemic is largely based."</ref>