The Verifiability theory of meaning was put forth in the early twentieth century by a group of logical positivists. The verifiability theory was based upon the verifiability principle, which states: "A statement is literally meaningful (it expresses a proposition) if and only if it is either analytic or empirically verifiable." If it failed that test, then it was held to be literally meaningless-to be nothing but a useless sound or babble-according to those who espoused the verifiability principle.
Adherents of the verifiability principle claimed that all statements of religion, spirituality, metaphysics, and ethics were literally meaningless-they were like meaningless noises, without any content that could be either true or false. In spite of their strenuous efforts, the verifiability principle and the philosophical movement behind it collapsed since the verifiability principle was self-refuting. The verifiability principle was not empirically verifiable nor was it an analytic statement such as the statements of logic and mathematics.
Development of the verifiability principle
David Hume (1711-1776) presented a view that was a forerunner of the verification principle. He argued that all meaningful concepts depended on sense experience and/or basic "relations among ideas" (logical relations mostly, also mathematics); if something could not be traced back to one or the other of these then, he claimed, it was meaningless.
In Hume's famous words:
When we run over libraries, persuaded of these principles, what havoc must we make? If we take in our hand any volume; of divinity or school metaphysics, for instance; let us ask, Does it contain any abstract reasoning concerning quantity or number? No. Does it contain any experimental reasoning concerning matter of fact and existence? No. Commit it then to the flames: for it can contain nothing but sophistry and illusion (Hume, "Enquiry Concerning Human Understanding," Section XII, Part III).
The logical positivists of the Vienna Circle and their followers (the so-called verificationists) used the verifiability principle or theory to build upon the theory of language that Ludwig Wittgenstein had introduced in his Tractatus Logico-Philosophicus. According to the Tractatus, "The world is the totality of facts, not of things" (proposition 1.1), "What is the case-a fact-is the existence of states of affairs" (prop. 2), "In a proposition a thought finds an expression that can be perceived by the senses" (3.1), "A proposition is a picture of reality" (4.01), "The simplest kind of proposition, an elementary proposition, asserts the existence of a state of affairs" (4.21), and "If an elementary proposition is true, the state of affairs it pictures or describes exists; if an elementary proposition is false, the state of affairs it pictures or describes does not exist" (4.25).
A. J. Ayer's famous book, Language, Truth, and Logic, was based on the verification principle and presented a forceful and highly influential account of it.
The classification terms analytic and synthetic, as used by Immanuel Kant, have been attacked as unsustainable and fallen into disuse. But, in essence, the positivists accepted that distinction and equated Kant's synthetic statements with empirical knowledge. If an empirical statement is true, they claimed, it must be in principle empirically verifiable, and if an empirical statement is false, it must be in principle empirically falsifiable.
Influence of the verifiability principle
While it lasted, the verifiability principle, or verifiability theory of meaning, had an enormous influence. As expressed in the quotation above from Hume, those who held to the verifiability principle issued claims and and expressed strongly held beliefs that statements of ethics, religion, aesthetics, and metaphysics were literally meaningless-like noises or meaningless babble-or at best had only emotive content and force.
The rise and prominence of emotivism as a theory of ethics was just one of the important consequence of the adoption of, and belief in, the verification principle. Since statements of ethics (and religion, metaphysics, and aesthetics) are not verifiable by the criteria set forth in the verifiability principle, those statements-according to anyone who held to the verifiability principle-must be literally meaningless, and ethics can then be only an expression of emotion. Thus, the claim, "X is ethically good" can only mean "I approve of X."
The enormous effort directed toward the elimination of metaphysics-as well as the great emotional attachment to that program-on the part of the logical positivists flowed out of their commitment to the verifiability principle and their strong belief that unverifiable statements are literally meaningless, and thus a bane to language and thought.
Collapse of the verifiability principle
The verifiability principle itself, however, is neither empirically verifiable nor is it analytic. Thus the verifiability principle is, strictly speaking, self-refuting.
In the early days of the logical positivists and the Vienna Circle and their followers, they did not recognize or realize the existence of this problem. Later there were enormous efforts by numerous logical positivists-Hempel, Carnap, and others-to develop a version of the verifiability principle that would withstand logical scrutiny and criticism, but those efforts always failed.
Eventually, those who wished to hold to the verifiability principle could present it only as a recommendation, not as something that could be proved or supported with either logic or good argument.
With that, the verifiability principle, or the verifiability theory of meaning, collapsed, and no knowledgeable philosopher or theorist today-that is, one who knows about the history of failure of all efforts to provide a logically sustainable verifiability principle and knows about its self-contradictory nature-holds to it any longer. But while it lasted, it had an enormous influence, leading to claims and strongly held beliefs that statements of ethics, religion, aesthetics, and metaphysics were meaningless or had only emotive content and force.
The verifiability theory of meaning is also closely related to the correspondence theory of truth.
- Ayer, A.J. Language, Truth, and Logic. London: V. Gollancz, 1936. ISBN 0141186046
- Hempel, Carl Gustav. Aspects of Scientific Explanation, and Other Essays in the Philosophy of Science. New York: Free Press, 1965.
- Hempel, Carl Gustav. "Problems and Changes in the Empiricist Criterion of Meaning," Review International de Philosophie 41 11(1950), pages 41-63.
- Hume, David, ed. An Enquiry Concerning Human Understanding. Oxford: Oxford University Press, 1999. ISBN 0198752490
- Quine, Willard Van Orman. "Two Dogmas of Empiricism," Orig. pub. in The Philosophical Review 60 (1951): 20-43.
- Sarkar, Sahotra, ed. Logical Empiricism at Its Peak: Schlick, Carnap, and Neurath. New York: Garland Pub., 1996. ISBN 0815322631
- Wittgenstein, Ludwig. Tractatus Logico-Philosophicus. London: Routledge, 2001. ISBN 0415254086
All links retrieved January 20, 2016.
- Vienna Circle, Stanford Encyclopedia of Philosophy.
- Vienna Circle, The Internet Encyclopedia of Philosophy.