In his essay The Philosophical Origins of Austrian Economics, David Gordon describes how Austrian economics arose in opposition to the German Historical School and then had to counter the logical positivism of the Vienna Circle. Gordon believes that the influence of logical positivism prevents most economists from accepting praxeology and Austrian economics. However, in my view, mainstream economists are often right to reject the Austrian school, particularly when its proponents turn their minds to matters of logic and philosophy. On such matters, Austrian economists too often do more harm than good, and taint good economics with bad philosophy. The section of the essay I wish to focus on is toward the end where Gordon discusses Mises’ rejection of the verification criterion:
It is easy to see that Mises’ reaction to the verifiability criterion would be the same. Praxeology arrives at truth by deduction. If someone wishes to define “meaning” so that the conclusions of praxeology are empirically meaningless, why should he care? To this an obvious rejoinder suggests itself. The logical positivists did not view their criterion of meaning as an arbitrary proposal, to be dismissed by anyone not sharing the Circle’s affinities. On the contrary, they claimed that their position was well supported. Are they correct?
I do not think so. In point of fact, the criterion is worthless, since every statement comes out verifiable under it. Suppose that p is a non-controversially verifiable statement, e.g., “there is a chair in this room.” Let us take q to be a statement logical positivists reject as meaningless. A good example is one that Rudolf Carnap held up to ridicule when he called for an end to metaphysics. He cited the following from Martin Heidegger’s Being and Time (1927): “The not nothings itself.” I shall not attempt to explain this: one can see why Carnap presented it as a paradigm instance of a meaningless statement.
Does the verification principle eliminate it? Surprisingly, it does not. From p, we deduce p or q. (This step is non-controversial.) Assuming that a logical consequence of a verifiable proposition is itself verifiable, (p or q) is verifiable. Further, if p is verifiable, then the negation of p is verifiable; this principle seems difficult to question. Now, consider this argument:
p or q
not -p
q
This argument is valid, and each of its premises is verifiable. Then, q is a logical consequence of verifiable propositions, and it, too, is verifiable. Clearly, if the verification criterion cannot eliminate “the not nothings itself,” it is not worth very much.
Gordon rightly explains that if p is verifable, then p v q is verifiable. However, his claim that “if p is verifiable, then the negation of p is verifiable” is problematic; the negation of a verifiable proposition is not necessarily verifiable. Gordon argues that “this principle seems difficult to question,” so a charitable interpretation of the claim is that by p he is referring specifically to the proposition “there is a chair in this room.” Assuming this proposition refers to a sufficiently small, well lit room and relatively large, undisguised chair, both the proposition and its negation are verifiable. In contrast, if p referred to the proposition “there is a chair in the solar system,” then ~p would be unverifiable, since while an entire room may be observable, the entire solar system is not (at least not for the purpose of finding a relatively small object like a chair). Gordon asks us to consider this argument:
p v q, ~p |= q
But why? The verified statement in the above argument is ~p, so the verificationist has no business including the formula p v q among his premises. Without verifying p or q independently, p v q is unverified. Gordon seems to be under the impression that both p v q and p can be introduced as premises merely because they are verifiable. A verificationist, meanwhile, would maintain that only premises that have actually been verified (not those that are merely verifiable) are eligible. How might a verificationist have verified p v q to include it among his premises? If p v q has been deduced from the verification of p, then including ~p in the premises is merely a contradiction introduced by Gordon, and if p v q has been deduced from the verification of q, then the premise ~p is irrelevent, because q has already been independently verified.
Although I previous urged a charitable interpretation of Gordon, his later application of the same argument to falsificationism seems to betray a fundamental misunderstanding of logic:
A falsification criterion fairs no better. If p is falsifiable, then (p and q) is falsifiable. Once more, not-p should be falsifiable if p is, though Karl Popper has implausibly denied this. By an argument parallel with that for verification, we conclude that q is falsifiable.
Once more, he states, without qualification, that “not-p should be falsifiable if p is,” but the negation of an existential proposition is logically equivalent to a universal proposition:
~Ex[Fx] =||= Ax[~Fx]
According to Gordon, if p refers to the verifiable proposition “there exists a white swan,” then ~p is also verifiable, but the proposition “there does not exist a white swan,” is logically equivalent to “all swans are non-white.” Therefore, if Gordon’s argument were a valid “criticism” of either verificationism or falsificationism, then he has inadvertantly demonstrated that the universal claims of scientific theories can indeed by verified by observation; rather than undermining the logical positivist program, Gordon would have removed their longest standing obstacle: the problem of induction. Karl Popper’s “implausible denial” was simply the application of standard textbook logic; Gordon merely erred by assuming that because the negation of his particular example of a verifiable statement (i.e. “there is a chair in this room”) was verifiable, that the negation of all verifiable statements are verifiable–it seems that apriorists can commit the inductive fallacy too!
Gordon’s argument is not valid. He betrays a funamental misunderstanding of quantitative logic and misrepresents his opponents’ position. Austrian economics deserves better defenders than this, especially from its flagship instititution.
