Page 67 - Encyclopedia of Philosophy of Language

knowledge, making a sharp distinction between meta- physics and science.
1. Cognitive Significance
The fundamental problem for these opponents of idealism was how to separate assertions that are wor- thy of our attention from those that are not. What principled basis could they give for declaring 'Jupiter has natural satellites' acceptable, but The Absolute is active' not? They sought the answer to this question by focusing on the general problem of meaning or cognitive significance. The question of how to separate science from unacceptable metaphysics depended on an answer to the question of when a statement is meaningful or cognitively significant.
In his Tractatus Logico-Philosophicus, Wittgenstein maintained that the claims of metaphysics are non- sense and that the only propositions which are sayable are those of natural science. Subsequently, empiricists tried to identify two different ways in which cognitive significance can be attained. Analytic statements are meaningful because their truth depends on the accepted conventions about how to use words. So 'All bachelors are unmarried' was said to be meaningful because it is true in virtue of the way words like 'bach- elor' and 'unmarried' are used in English. Analytic truths can be thought of as following from the truths of logic together with certain linguistic conventions (what Carnap called 'meaning postulates'). If all of mathematics could be reduced to logic, its truths, cen- tral as they are to the sciences, would belong to the category of the meaningful. All other statements are meaningful, according to the 'verifiability principle,' only insofar as they are in principle capable of being verified by (actual or possible) experience. The trouble with 'The Absolute is active' is that there is no set of observations that could, even in principle, establish its truth.
2. TheVerifiabilityPrinciple
The verifiability principle provided verificationism with both a theory of meaning and a solution to what Karl Popper called the 'problem of demarcation,' the problem of how to separate science from nonscience. For verificationists, the separation of science from nonscience coincided with the separation of sense from nonsense. As well as metaphysics, much of what had traditionally been part of epistemology, ethics, and other branches of philosophy, was now said to consist of nonscientific, meaningless claims. Con- structions like 'Murder is wrong,' may have an emo- tive content, but are, at best, pseudostatements de- void of factual meaning.
Early formulations of the verifiability principle restricted meaningfulness to statements capable of conclusive verification. Under this formulation, the principle entails that a nonanalytic statement is mean- ingful if and only if some set of basic observation
statements entail (and are entailed by) the statement in question. This formulation of the principle, however, was too restrictive to serve the veri- ficationists' purposes. In particular, this formulation renders all universal laws of science nonscientific and meaningless. No unrestricted universal statement can be conclusively established on the basis of a limited number of observations alone. Since verifiability was intended to legitimize science, as well as condemn metaphysics, emasculating science by declaring all scientific laws to be nonsense was unacceptable. In Language, Truth and Logic, A. J. Ayer weakened the principle to make verifiability equivalent to con- firmability. This meant that a nonanalytic statement is meaningful just in case it is possible that there be some evidence that counts in favor of the truth of that statement. On Ayer's account, an empirically mean- ingful statement is one that can be conjoined with suitable auxiliary hypotheses to derive observational consequences that are not derivable from the auxiliary hypotheses alone.
While this weaker criterion of empirical meaning gives the verdict that scientific laws are empirically meaningful, it also gives the verdict that 'The Absolute is active' is meaningful because we can take 'If the Absolute is active, then Rover is brown' as an auxili- ary hypothesis and with the two of these statements derive 'Rover is brown,' which is entailed by neither the statement in question nor the auxiliary hypothesis alone. A further attempt was to suggest that all empiri- cally meaningful statements can be reduced to state- ments in a suitably restricted language whose primitive predicates all designate only characteristics of immediate experience. Other variations on the theme of formulating an acceptable criterion of mean- ingfulness in terms of verifiability were proposed, but each had the weakness of either excluding too much or too little from the realm of the meaningful.
3. Falsifiability
According to Karl Popper, theories like astrology are defective not because they are not amenable to con- firmation but because they are too confirmable. No matter what happens, pseudoscientific claims are com- patible with the outcome. Astrology is pseudo- scientific precisely because it is confirmed by every- thing and falsifiable by nothing. In contrast, Einstein's theory of relativity makes risky predictions that could turn out to be incorrect. Thus, Popper suggested that the hallmark of science is not any form of veri- fiability, butfalsifiability. For him, the issue of sepa- rating science from pseudoscience and the issue of separating sense from nonsense were independent issues, the former being a genuine philosophical prob- lem while the latter is a typical philosophical pseudo- problem. Popper was concerned only with the line of demarcation between science and pseudoscience. His critiques of the general confirmationist or inductivist
Verificationism
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