Page 68 - Encyclopedia of Philosophy of Language

Language, Metaphysics, and Ontology
approaches to science were misconstrued as alter- native proposals about meaning and many of his criti- cisms were unheeded for several decades.
4. Verificationism and Semantic Theory
Verificationism is still a prevalent doctrine in semantic theory. Verificationismin semantic theory is the doc- trine that the meaning of a statement is at least par- tially a function of the evidence one has for that statement. Michael Dummett's verificationist seman- tics, sometimes called semantic antirealism, claims that the meaning of a statement is the conditions under which a speaker has sufficient justification for assert- ing it. However, Dummett's project is not to dis- tinguish science from pseudoscience or sense from nonsense. Rather, it is to account for linguistic knowl- edge. If language is to be learnable, he argues, meanings are things to which speakers will have sufficient access in order to associate those meanings with the appropriate statements. By contrast, truth- conditional semantics allows that statements may be true(orfalse)eventhoughthosewhounderstandthem may be in principle incapable of recognizing this. Thus, contemporary verificationists explicate sem- antic properties in terms of epistemological properties. For them, the theory of meaning is just the theory of linguistic understanding; and meanings are not enti-
ties, but structured practices of competent speakers of a language.
In ways that earlier verificationists did not fully appreciate, verificationist (antirealist) semantics has implications for the proper form of logical theory, and for acceptable metaphysical theses. If statements do not have truth conditions that transcend verification, then to assert a statement is equivalent not to the assertion that the statement is true, but to the assertion that the statement is justified. The assertion that p is equivalent to the assertion that 'p' is justified. It fol- lows that the assertion that ~ p is equivalent to the assertion that '~p' is justified. Consider now the classical law of excluded middle, which says that every instance of 'p v ~ p ' is true. If verificationist sem- antics is adopted, this reduces to the claim that it is
always true that either 'p' is justified or else ' ~ p' is justified. But, there are many statements we have nei- ther sufficient reason to assert nor sufficient reason to deny. For them, the proper action is refusal either to assert or deny. Accordingly, excluded middle is rejected by contemporary antirealists along with the
classical logic in which this law is embedded.
It is widely recognized that a thoroughgoing empiri- cist semantics requires a radical rethinking of the nat- ure of valid inference. If truth is thought to be closely associated with warranted assertibility, then the sem- antic principle of bivalence, that every statement is either true or false, must also be rejected by the veri-
ficationist for parallel reasons.
Verificationism has parallel consequences for meta-
physics. If some statements are neither true nor false, and truth requires metaphysical truthmakers (be they cognizer-independent facts or cognizer-dependent epi- stemic conditions), then—as it were—the world has metaphysical gaps. Suppose 'p' is such a statement. There is no truthmaker for 'p' and there is no truth- makerfor'~p'(thereisnofactofthematter).Far from Verificationism laying all metaphysical claims to rest, it appears to carry with it its own metaphysical commitments.
See also: Analyticity; Meaning Postulate; Falsi-
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ficationism; Realism.
Bibliography
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