Editing Logical positivism (section)

==Criticism==

In the post-war period, key tenets of logical positivism, including the [[verificationism|verifiability criterion]], [[analytic-synthetic distinction]] and [[Logical positivism#Observation-theory distinction|observation-theory distinction]], drew escalated criticism.<ref name="Bunge1996"/> This would become sustained from various directions by the 1950s,<ref name=Sarkar2005>{{cite book |first1=S |last1=Sarkar |first2=J |last2=Pfeifer |year=2005 |title=The Philosophy of Science: An Encyclopedia |volume=1 |publisher=Taylor & Francis |isbn=978-0415939270 |url=https://books.google.com/books?id=od68ge7aF6wC&pg=PA83 |page=83}}</ref> so that, even among fractious philosophers who disagreed on the general objectives of [[epistemology]], most would concur that the logical positivist program had become untenable.<ref name=Putnam1985>{{cite book |author=Hilary Putnam |year=1985 |title=Philosophical Papers: Volume 3, Realism and Reason |publisher=Cambridge University Press |isbn=978-0521313940 |lccn=lc82012903}}</ref> Notable critics included [[Karl Raimund Popper|Karl Popper]], [[Willard Van Orman Quine|W. V. O. Quine]], [[Norwood Russell Hanson|Norwood Hanson]], [[Thomas Samuel Kuhn|Thomas Kuhn]], [[Hilary Putnam]],<ref name=sep-vienna-circle/> as well as [[J. L. Austin]], [[Peter Strawson]], [[Nelson Goodman]] and [[Richard Rorty]].<ref>{{cite journal |last=Franco |first=Paul L. |year=2018 |title= Ordinary Language Criticisms of Logical Positivism |journal=HOPOS: The Journal of the International Society for the History of Philosophy of Science |volume=8 |issue=1 |pages=157-190}}</ref> [[Carl Hempel|Hempel]] himself became a major critic from within the movement, denouncing the positivist thesis that empirical knowledge is restricted to ''basic statements'', ''observation statements'' or ''protocol statements''.<ref name=sep-hempel>{{cite encyclopedia |first=James |last=Fetzer |editor=Edward N. Zalta |year=2012 |title=Carl Hempel |encyclopedia=The Stanford Encyclopedia of Philosophy |edition=Summer 2012 |url=https://plato.stanford.edu/entries/hempel/#SciRea |access-date=31 August 2012}}</ref>

===Karl Popper===
[[Karl Popper]], a graduate of the [[University of Vienna]], was an outspoken critic of the logical positivist movement from its inception. In ''Logik der Forschung'' (1934, published in English in 1959 as ''[[The Logic of Scientific Discovery]]'') he attacked [[verificationism]] directly, contending that the [[problem of induction]] renders it impossible for [[hypothesis|scientific hypotheses]] and other [[universal generalization|universal statements]] to be verified conclusively. Any attempt to do so, he argued, would commit the fallacy of [[affirming the consequent]], given that verification cannot—in itself—exclude alternative valid explanations for a specific phenomenon or instance of observation.<ref>{{cite book|first=Samir |last=Okasha |title=The Philosophy of Science: A Very Short Introduction |location=New York |publisher=Oxford University Press |year=2002 |page=23}}</ref> He would later affirm that the content of the verifiability criterion cannot be empirically verified, thus is meaningless by its own proposition and ultimately [[self-refuting idea|self-defeating]] as a principle.<ref name=Piep>{{cite encyclopedia |url=https://www.iep.utm.edu/pop-sci/#H3 |title=Karl Popper: Philosophy of Science |last=Shea |first=Brendan |encyclopedia=Internet Encyclopedia of Philosophy |access-date=May 12, 2019}}</ref>

In the same book, Popper proposed ''[[falsifiability]]'', which he presented, not as a criterion of ''cognitive meaning'' like verificationism (as commonly misunderstood),<ref name="Hacohen">{{cite book |title=Karl Popper: The Formative Years, 1902–1945: Politics and Philosophy in Interwar Vienna |last=Hacohen |first=Malachi Haim |year=2000 |publisher=Cambridge University Press |location=Cambridge |pages=212-13}}</ref> but as a criterion to distinguish scientific from non-scientific statements, thereby to [[demarcation problem|demarcate the boundaries of science]]. Popper observed that, though universal statements cannot be verified, they can be falsified, and that the most productive scientific theories were apparently those that carried the greatest 'predictive risks' of being falsified by observation.<ref name=PopperAE>{{cite book |title=Conjectures and Refutations: The Growth of Scientific Knowledge |last=Popper |first=Karl |year=1962 |publisher=Routledge |edition=2nd |pages=34-37}}</ref> He would conclude that the [[scientific method]] should be a [[hypothetico-deductive model]], wherein scientific hypotheses must be falsifiable (per his criterion), held as provisionally true until proven false by observation, and are ''corroborated'' by supporting evidence rather than verified or confirmed.<ref name=Popper>{{cite book |last=Popper |first=Karl |title=The Logic of Scientific Discovery |doi=10.4324/9780203994627 |publisher=Routledge |location=London |year=2005 |edition=2nd}}</ref>

In rejecting neo-positivist views of cognitive meaningfulness, Popper considered [[metaphysics]] to be rich in meaning and important in the origination of scientific theories and [[value system]]s to be integral to science's quest for truth. At the same time, he disparaged [[pseudoscience]], referring to the [[confirmation bias]]es that embolden support for unfalsifiable conjectures (notably those in [[psychology]] and [[psychoanalysis]]) and ''[[ad hoc]]'' arguments used to entrench predictive theories that have been proven conclusively false.<ref name=PopperAE/>

===Willard V. O. Quine===

In his influential 1951 paper ''[[Two Dogmas of Empiricism]]'', American philosopher and [[logicism|logicist]] [[Willard Van Orman Quine]] challenged the [[Logical positivism#Analytic-synthetic distinction|analytic-synthetic distinction]].  Specifically, Quine examined the concept of [[Two Dogmas of Empiricism#Analyticity and circularity|analyticity]], determining that all attempts to explain the idea reduce ultimately to [[circular reasoning]]. He would conclude that, if analyticity is untenable, so too is the neo-positivist proposition to redefine its boundaries.<ref>{{cite journal |first=Willard V. O. |last=Quine |title=Two Dogmas of Empiricism |journal=Philosophical Review |year=1951 |volume=60 |pages=20–43}} collected in {{cite book |first=Willard V. O. |last=Quine |title=From a Logical Point of View |location=Cambridge MA |publisher=Harvard University Press |year=1953}}</ref> Yet [[Rudolf Carnap|Carnap]]'s reconstruction of analyticity was necessary for logic and mathematics to be deemed meaningful under verificationism. Quine's arguments encompassed numerous criticisms on this topic he had articulated to Carnap since 1933.<ref name=IEPQ>{{cite encyclopedia |url=https://iep.utm.edu/quine-an/#H2 |title=Willard Van Orman Quine: The Analytic/Synthetic Distinction |last=Rocknak |first=Stefanie |encyclopedia=Internet Encyclopedia of Philosophy |access-date= July 14, 2024}}</ref> His work effectively pronounced the verifiability criterion untenable, threatening to uproot the broader logical positivist project.<ref>{{cite book |last=Shieh |first=Sanford |chapter=Logical Positivism and Quine |title=A Companion to the Philosophy of Language |year=2012 |publisher=Routledge |pages=869-872 |editor1=D. Graff Fara |editor2=G. Russell}}</ref>

===Norwood Hanson===

In 1958, [[Norwood Russell Hanson|Norwood Hanson]]'s ''Patterns of Discovery'' characterised the concept of [[theory-laden|theory-ladenness]]. Hanson and [[Thomas Kuhn]] held that even direct observations are never truly neutral in that they are ''laden with theory'', i.e. influenced by a system of theoretical [[presuppositions]] that function as an interpretative framework for the [[sense data|senses]].<ref>{{cite book |title=Beyond Positivism: Economic Methodology in the 20th Century |last=Caldwell|first=Bruce|pages=47-48 |year=1994 |publisher=Routledge |location=London}}</ref> Accordingly, individuals subscribed to different theories might report radically different observations even as they investigate the same phenomena. Hanson's thesis attacked the [[Logical positivism#Observation-theory distinction|observation-theory distinction]], which draws a dividing line between observational and non-observational (theoretical) language. More broadly, its findings challenged the central-most tenets of [[empiricism]] in questioning the infallibility and objectivity of empirical observation.<ref>{{cite encyclopedia |first=Nora Mills |last=Boyd |editor=Edward N. Zalta |year=2009 |edition=2021 |title=Theory and Observation in Science |encyclopedia=The Stanford Encyclopedia of Philosophy |url=https://plato.stanford.edu/entries/science-theory-observation/ |access-date=29 January 2025}}</ref>

===Thomas Kuhn===

[[Thomas Samuel Kuhn|Thomas Kuhn]]'s landmark book of 1962, ''[[The Structure of Scientific Revolutions]]''—which discussed [[paradigm shift]]s in [[fundamental interactions|fundamental physics]]—critically undermined confidence in scientific [[foundationalism]].<ref>{{cite book |title=Philosophy of Science: A Very Short Introduction |last=Okasha|first=Samir|year=2002 |chapter=Scientific Change and Scientific Revolutions |publisher=Oxford University Press |location=Oxford}}</ref> Kuhn proposed in its place a [[coherentism|coherentist]] model of science, whereby scientific progress revolves around cores of established, coherent ideas which periodically undergo abrupt revolutionary changes.<ref>{{cite journal |last=Daston |first=Lorraine |year=2020 |title=Thomas S. Kuhn, The Structure of Scientific Revolutions (1962) |url=http://dx.doi.org/10.1215/08992363-8090152 |journal=Public Culture |volume=32 |issue=2 |pages=405–413 |doi=10.1215/08992363-8090152 |issn=0899-2363}}</ref>

Though foundationalism was often considered a constituent doctrine of logical positivism (and Kuhn's thesis an [[epistemological]] criticism of the movement) such views were simplistic:<ref>{{harvnb|Uebel|2008}} 3.3</ref> In the 1930s, [[Otto Neurath|Neurath]] had argued for the adoption of [[coherentism]], famously comparing the progress of science to [[Neurath's boat|reconstruction of a boat at sea]].<ref name=ONPSP>{{cite book|title=Otto Neurath: Philosophy Between Science and Politics |volume=38 |series=Ideas in Context |first1=Nancy |last1=Cartwright |author-link1=Nancy Cartwright (philosopher) |first2=Jordi |last2=Cat |first3=Lola |last3=Fleck |first4=Thomas E. |last4=Uebel |publisher=Cambridge University Press |year=2008 |isbn=978-0521041119 |chapter=On Neurath's Boat |pages=89–94}}</ref> [[Rudolf Carnap|Carnap]] had entertained foundationalism from 1929 to 1930, but he, [[Hans Hahn (mathematician)|Hans Hahn]] and others would later join Neurath in converting to a coherentist philosophy. The [[Logical positivism#Vienna and Berlin Circles|conservative wing]] of the [[Vienna Circle]] under [[Moritz Schlick]] subscribed to a form of foundationalism, but its principles were defined unconventionally or ambiguously.<ref>{{harvnb|Uebel|2008}} 3.3 Uebel writes, "Even Schlick conceded, however, that all scientific statements were fallible ones, so his position on foundationalism was by no means the traditional one. The point of his “foundations” remained less than wholly clear and different interpretation of it have been put forward."</ref>

In some sense, Kuhn's book unified science, but through historical and social assessment rather than by [[Logical positivism#Unity of science|networking the scientific specialties]] using epistemological or [[linguistics|linguistic]] models.<ref name=Novick-p526>{{harvnb|Novick|1988}} pp. 526–27</ref> His ideas were adopted quickly by scholars in non-scientific disciplines, such as the social sciences in which neo-positivists were dominant,<ref name=Novick-p546/> ushering academia into [[postpositivism]] or postempiricism.<ref name=Novick-p526/>

===Hilary Putnam===

In his critique of the [[received view of theories|received view]] in 1962, [[Hilary Putnam]] attacked the [[Logical positivism#Observation-theory distinction|observation-theory distinction]].<ref>{{cite book |title=Logic, Methodology, and Philosophy of Science |last=Putnam |first=Hilary |pages=240–251 |chapter=What Theories are Not |year=1962 |publisher=Stanford University Press |location=Stanford |editor1= E. Nagel |editor2=P. Suppes |editor3=A. Tarski }}</ref> Putnam proposed that the division between "observation terms" and "theoretical terms" was untenable, determining that both categories have the potential to be [[theory-laden]]. Accordingly, he remarked that observational reports frequently refer to theoretical terms in practice.<ref>{{cite book |first=Hilary |last=Putnam |chapter=Problems with the observational/theoretical distinction |title=Scientific Inquiry |editor=Robert Klee |location=New York |publisher=Oxford University Press |year=1999 |pages=25–29}}</ref> He illustrated cases in which observation terms can be applied to entities that [[Rudolf Carnap|Carnap]] would classify as [[unobservable]]s. For example, in [[Isaac Newton|Newton]]'s [[corpuscular theory of light]], observation concepts can be applied to the consideration of both [[Orders of magnitude (volume)#Sub-microscopic|sub-microscopic]] and macroscopic objects.<ref>{{cite encyclopedia |last=Andreas |first=Holger |editor=Edward N. Zalta |year=2013 |edition=August 2021 |title=Theoretical Terms in Science |encyclopedia=The Stanford Encyclopedia of Philosophy |url=https://plato.stanford.edu/entries/theoretical-terms-science/ |access-date=30 January 2025}}</ref>

Putnam advocated [[scientific realism]], whereby scientific theory describes a [[reality|real world]] existing independently of the senses. He rejected positivism, which he dismissed as a form of [[idealism|metaphysical idealism]], in that it precluded any possibility to acquire knowledge of the unobservable aspects of nature. He also spurned [[instrumentalism]], according to which a scientific theory is judged, not by whether it corresponds to reality, but by the extent to which it allows empirical predictions or resolves conceptual problems.<ref name="Friedman-pxii"/>