Verificationism

Verificationism, also known as the verification principle or the verifiability criterion of meaning, is the philosophical doctrine which asserts that a statement is meaningful only if it is either empirically verifiable (i.e. confirmed through the senses) or a truth of logic (e.g., tautologies).

Verificationism rejects statements of metaphysics, theology, ethics, and aesthetics, as cognitively meaningless. ^{[1] [2]} Such statements may be meaningful in influencing emotions or behavior, but not in terms of conveying truth value, information, or factual content. ^[3] Verificationism was a central thesis of logical positivism, a movement in analytic philosophy that emerged in the 1920s by philosophers who sought to unify philosophy and science under a common naturalistic theory of knowledge.

Origins

Although earlier philosophical principles which aim to ground scientific theory in some verifiable experience are found within the work of American pragmatist C.S. Peirce and that of French conventionalist Pierre Duhem, ^[4] who fostered instrumentalism, ^[5] the project of verificationism was launched by the logical positivists who, emerging from the Berlin Circle and the Vienna Circle in the 1920s, sought an epistemology whereby philosophical discourse would be, in their perception, as authoritative and meaningful as empirical science.

Logical positivists garnered the verifiability criterion of cognitive meaningfulness from Ludwig Wittgenstein's philosophy of language posed in his 1921 book Tractatus , ^[6] and, led by Bertrand Russell, sought to reformulate the analytic–synthetic distinction in a way that would reduce mathematics and logic to semantical conventions. This would be pivotal to verificationism, in that logic and mathematics would otherwise be classified as synthetic a priori knowledge and defined as "meaningless" under verificationism.

Seeking grounding in such empiricism as of David Hume, ^[7] Auguste Comte, and Ernst Mach—along with the positivism of the latter two—they borrowed some perspectives from Immanuel Kant, and found the exemplar of science to be Albert Einstein's general theory of relativity.

Revisions

Logical positivists within the Vienna Circle recognized quickly that the verifiability criterion was too stringent. Notably, universal generalizations are empirically unverifiable, such that, under verificationism, vast domains of science and reason, such as scientific hypothesis, would be rendered meaningless. ^[8]

Rudolf Carnap, Otto Neurath, Hans Hahn and Philipp Frank led a faction seeking to make the verifiability criterion more inclusive, beginning a movement they referred to as the "liberalization of empiricism". Moritz Schlick and Friedrich Waismann led a "conservative wing" that maintained a strict verificationism. Whereas Schlick sought to reduce universal generalizations to frameworks of 'rules' from which verifiable statements can be derived, ^[9] Hahn argued that the verifiability criterion should accommodate to less-than-conclusive verifiability. ^[10] Among other ideas espoused by the liberalization movement were physicalism, over Mach's phenomenalism, coherentism over foundationalism, as well as pragmatism and fallibilism. ^{[8] [11]}

In 1936, Carnap sought a switch from verification to confirmation. ^[8] Carnap's confirmability criterion (confirmationism) would not require conclusive verification (thus accommodating for universal generalizations) but allow for partial testability to establish "degrees of confirmation" on a probabilistic basis. Carnap never succeeded in formalizing his thesis despite employing abundant logical and mathematical tools for this purpose. In all of Carnap's formulations, a universal law's degree of confirmation is zero. ^[12]

That same year saw the publication of A. J. Ayer's work, Language, Truth and Logic , in which he proposed two types of verification: strong and weak. This system espoused conclusive verification, yet accommodated for probabilistic inclusion where verifiability is inconclusive. Ayer also distinguished between practical and theoretical verifiability. Under the latter, propositions that cannot be verified in practice would still be meaningful if they can be verified in principle. ^{[13] [14]}

Criticisms

Philosopher Karl Popper, a graduate of the University of Vienna, though not a member within the ranks of the Vienna Circle, was among the foremost critics of verificationism. He identified three fundamental deficiencies in verifiability as a criterion of meaning: ^[15]

• Verificationism rejects universal generalizations, like "all swans are white," as meaningless. Popper argues that while universal statements cannot be verified, they can be proven false, a foundation on which he was to propose his criterion of falsifiability.
• Verificationism allows existential statements, like “unicorns exist”, to be classified as scientifically meaningful, despite the fact that there is no way of definitively showing that they are false and one could possibly find one somewhere not yet inspected.
• Verificationism is meaningless by virtue of its own criterion because it cannot be empirically verified. Thus the concept is self-defeating.

Popper regarded scientific hypotheses to be never completely verifiable, as well as not "confirmable" under Rudolf Carnap's thesis. ^{[6] [16]} Popper also found that some non-scientific, metaphysical, ethical and aesthetic statements were, indeed, rich in meaning and important in the origination of scientific theories. ^[6]

Other philosophers also voiced their own criticisms of verificationism:

• The 1951 article "Two Dogmas of Empiricism", by Willard Van Orman Quine, found no suitable explanations for the concept of analyticity in that they reduced ultimately to circular reasoning. This served to uproot the analytic/synthetic division pivotal to verificationism. ^[17]
• Carl Hempel (1950, 1951) demonstrated that the verifiability criterion was not justifiable in that it was too strong to accommodate key proceedings within science, such as general laws and limits in infinite sequences. ^[18]
• In 1958, Norwood Hanson explained that direct observations are never truly neutral in that they are laden with theory. ie. Influenced by a system of presuppositions that act as an interpretative framework for those observations. Those subscribed to different theories might thus report radically different observations, even when they observe the same phenomena. ^[19]
• Thomas Kuhn's landmark book of 1962, The Structure of Scientific Revolutions —which discussed paradigm shifts in fundamental physics—critically undermined confidence in scientific foundationalism, ^[20] a theory commonly, if erroneously, attributed to verificationism. ^[21]

Falsifiability

Main article: Falsifiability

In The Logic of Scientific Discovery (1959), Popper proposed falsifiability, or falsificationism. Though formulated in the context of what he perceived were intractable problems in both verifiability and confirmability, Popper intended falsifiability, not as a criterion of meaning like verificationism (as commonly misunderstood), ^{[6] [22]} but as a criterion to demarcate scientific statements from non-scientific statements. ^[6]

Notably, the falsifiability criterion would allow for scientific hypotheses (expressed as universal generalizations) to be held as provisionally true until proven false by observation, whereas under verificationism they would be disqualified immediately as meaningless. ^[6]

In formulating his criterion, Popper was informed by the contrasting approaches of Albert Einstein and Sigmund Freud. Popper noticed that Einstein sought out data that would disprove his theories. He made predictions about future instances based upon the past, and then tried to learn more to test the validity of his hypothesis. Freud, on the other hand, selected data that could be shaped to fit his theories, and his theories were crafted to explain the past, not the future. For Popper, this clarified a key difference between science and pseudoscience. ^{[23] [24]}

Though falsificationism has been criticized extensively by philosophers for methodological shortcomings in its intended demarcation of science, ^[15] Popper has been the only philosopher of science often praised by many scientists. ^[16] Despite its problems, Popper's criterion was to ensure that scientific theory was henceforth to be anchored in empiricism ^[4] and logical positivists adopted Popper's criterion of falsifiability, catapulting Popper, initially a contentious misfit, to carry the richest philosophy out of interwar Vienna. ^[22]

Legacy

In 1967, John Passmore, a leading historian of 20th-century philosophy, wrote, "Logical positivism is dead, or as dead as a philosophical movement ever becomes". ^[25] Logical positivism's fall heralded postpositivism, where Popper's view of human knowledge as hypothetical, continually growing and open to change ascended ^[22] and verificationism, in academic circles, became mostly maligned. ^[4]

In a 1976 TV interview, A. J. Ayer, who had introduced logical positivism to the English-speaking world in the 1930s, ^[26] was asked what he saw as its main defects, and answered that "nearly all of it was false". ^[25] However, he soon said that he still held "the same general approach", referring to empiricism and reductionism, whereby mental phenomena resolve to the material or physical and philosophical questions largely resolve to ones of language and meaning. ^[25] In 1977, Ayer recognized that the verification principle was not widely accepted but acknowledged that it still held relevance and was being utilised. "The attitude of many philosophers reminds me of the relationship between Pip and Magwitch in Dickens's Great Expectations . They have lived on the money, but are ashamed to acknowledge its source". ^[4]

In the late 20th and early 21st centuries, the general concept of verification criteria—in forms that differed from those of the logical positivists—was defended by Bas van Fraassen, Michael Dummett, Crispin Wright, Christopher Peacocke, David Wiggins, Richard Rorty, and others. ^[4]

See also

• Epistemic theories of truth
• Newton's flaming laser sword
• Semantic anti-realism (epistemology)

Notes

1. "verification principle". Oxford Reference. Retrieved 2023-07-09.
2. "Logical Positivism Revisited" (PDF).
3. Editors of Encyclopædia Britannica, "Verifiability principle", Encyclopædia Britannica, Website accessed 12 Mar 2014.
4. C. J. Misak, Verificationism: Its History and Prospects (New York: Routledge, 1995), p. viii.
5. Miran Epstein, ch 2 "Introduction to philosophy of science", in Clive Seale, ed, Researching Society and Culture, 3rd edn (London: Sage Publications, 2012), pp. 18–19.
6. Karl Popper, ch 4, subch "Science: Conjectures and refutations", in Andrew Bailey, ed, First Philosophy: Fundamental Problems and Readings in Philosophy, 2nd edn (Peterborough Ontario: Broadview Press, 2011), pp. 338–42.
7. Despite Hume's radical empiricism, set forth near 1740, Hume was also committed to common sense, and apparently did not take his own skepticism, such as the problem of induction, as drastically as others later did [Antony G Flew, A Dictionary of Philosophy, rev 2nd edn (New York: St Martin's Press, 1984), "Hume", p. 156].
8. Sahotra Sarkar and Jessica Pfeifer, eds, The Philosophy of Science: An Encyclopedia, Volume 1: A–M (New York: Routledge, 2006), "Rudolf Carnap", p. 83.
9. Moritz Schlick, 1931, "Die Kausalität in der gegenwärtigen Physik", Die Naturwissen-schaften, 19: 145–162; transl. "Causality in Contemporary Physics" in Schlick 1979b, pp. 176–209
10. Hahn, Hans, 1933, Logik, Mathematik und Naturerkennen, Wien: Gerold, transl. "Logic, Mathematics, and Knowledge of Nature", in B. McGuiness 1987, pp. 24–45.
11. Antony G Flew, A Dictionary of Philosophy, rev 2nd edn (New York: St Martin's Press, 1984), "Neurath", p. 245.
12. Mauro Murzi "Rudolf Carnap (1891–1970)", Internet Encyclopedia of Philosophy, 12 Apr 2001.
13. Ayer, A.J. (1936). Language, Truth, and Logic (PDF). pp. 6–7.
14. "Ayer on the criterion of verifiability" (PDF). 29 November 2007. Retrieved 9 July 2023.
15. Shea, Brendan. "Karl Popper: Philosophy of Science". Internet Encyclopedia of Philosophy. Retrieved May 12, 2019.
16. Peter Godfrey-Smith, Theory and Reality: An Introduction to the Philosophy of Science (Chicago: University of Chicago Press, 2005), pp. 57–59.
17. Rocknak, Stefanie. "Willard Van Orman Quine: The Analytic/Synthetic Distinction". Internet Encyclopedia of Philosophy. Retrieved July 14, 2024.
18. James Fetzer, "Carl Hempel", in Edward N Zalta, ed, The Stanford Encyclopedia of Philosophy (Spring 2013).
19. Bruce Caldwell, Beyond Positivism: Economic Methodology in the 20th Century, rev edn (London: Routledge, 1994), pp. 47–48.
20. Samir Okasha, Philosophy of Science: A Very Short Introduction (New York: Oxford University Press, 2002) ch 5.
21. Thomas Uebel, "Vienna Circle", sec "3.3 Reductionism and foundationalism: Two criticisms partly rebutted", in Edward N Zalta, ed, The Stanford Encyclopedia of Philosophy (Summer 2012 edn).
22. Malachi Haim Hacohen, Karl Popper: The Formative Years, 1902–1945: Politics and Philosophy in Interwar Vienna (Cambridge: Cambridge University Press, 2000), pp. 212–13.
23. "Popper's Account of Scientific Theories". www.sfu.ca. Retrieved 2023-07-10.
24. Karl Popper, Science, & Pseudoscience: Crash Course Philosophy #8 , retrieved 2023-07-10
25. Oswald Hanfling, ch 5 "Logical positivism", in Stuart G Shanker, Philosophy of Science, Logic and Mathematics in the Twentieth Century (London: Routledge, 1996), pp. 193–94.
26. Chapman, S. (2009). Logical positivism. In S. Chapman, & C. Routledge, Key ideas in linguistics and the philosophy of language. Edinburgh University Press. Credo Reference: https://go.openathens.net/redirector/umb.edu?url=https%3A%2F%2Fsearch.credoreference.com%2Fcontent%2Fentry%2Fedinburghilpl%2Flogical_positivism%2F0%3FinstitutionId%3D766