I was just recently given this critique of praxeology, to which I wrote a response.
Here is the critique:
"Praxeology is founded on the premise that "humans act," & by "act," they exert their will with the intent to accomplish goals. Because this is taken as axiomatic - that is, because this proposition is taken as an independent, stand-alone, self-evident truth - by the Austrian school, it is argued that a whole system of thought can be derived from this axiom purely through deductive means, akin to any given branch of pure mathematics.
The problem is though, that this "axiom" is anything but self-evident. Many cognitive scientists believe that the will, intent, & goals are just illusions pre-fabricated by our brains, & indeed, Praxeology just assumes outright that we have free will. Now, whether or not those cognitive scientists are correct is beside the point - the fact that it's even *possible* that the action axiom is wrong means that if it's true, it's an *empirical* fact, not an axiomatic one. As such, Praxeological methodology is rendered invalid, & thus the study of human action, as well as of economics in general, must be conducted through largely inductive (empirical) means, like any other science.
Now, there's another angle to this, namely, Goedel's Incompleteness Theorem. The Incompleteness Theorem states that in any axiomatic system, there are always going to be true conclusions relevant to said system which can't be derived from the axiom(s). This means that Praxeology is subject to the Incompleteness Theorem. In other words, if the proposition that humans act is an axiom, then not everything which is true about human action can be derived from Praxeology; if, however, the proposition that humans act is an empirical fact, then everything which is true about human action can be inferred as an implication of said fact.
Not only does that mean that an empirical "Praxeology" would be more complete than an *a priori* one, but an *a priori* Praxeology is squarely at odds with reality, as it leads to the conclusion that not every implication of the proposition that humans act is really an implication thereof. And this isn't a flaw that can be contained to whatever conclusions that Praxeology can't reach, e
ither, for if one methodology leads to a partially accurate but false result, & another, radically different, methodology, leads to a true result, then it can be concluded that there is a rather profound flaw in the former methodology that casts a shadow on the whole enterprise.
To put it another way, conceiving of human action as axiomatic (assuming that from it you can derive all of its implications) leads to the conclusion that the action axiom cannot predict all of its own implications, & indeed, that only a radically different methodology *can,* so Praxeology is thoroughly self-refuting.
So there you go, two logical proofs that Praxeology is bunk."
Here is my response:
In response, I would first point out that in no way does praxeology assume "free will." Where our perceived goals and motivations come from is not the realm of inquiry of praxeology and is unrelated to the conclusions based on praxeologic methods. It does not matter if our will is an illusion, because praxeology studies only the results of what happens when and if people do act. The impetus to action is a different area of study. The criticism that "praxeology is actually empirically based" can apply equally to pure mathematics in this sense, because mathematics assumes such things as numbers into existence. One can argue equally well that this assumption is not "axiomatic," but that is simply pointless semantics. Wherever the idea comes from, it cannot simply be refuted in the world we live in, regardless of whether it might not be true in all conceivable universes.
Secondly, praxeology and economics by no means strictly limit themselves only to those things which can be deduced directly from the action axiom: there are many auxiliary postulates and assumptions involved. For example, we could study praxeology without the assumption that human beings value leisure time to some extent, but that would largely make such study useless. This assumption gives us all of the information we have on how labor is relevant to our economy. Goedel's Incompleteness Theorem certainly holds true: this is not in dispute, but it is irrelevant because so-called "praxeological economics" as practiced by the Austrian School is not "purely" axiomatic. It is simply based in an axiomatic framework. There is not some huge debate between defenders of "apriori praxeology" and "empirical praxeology" as holistic systems, as far as I'm aware, because no one simply defends a pure "apriori praxeology" as being the end of all praxeological study. The "empirical" assumptions give most of the breadth of praxeology qua economics, and that is recognized widely, I believe, by those calling themselves "praxeologists." The crucial point is that the auxiliary assumptions involved treated appropriately within the axiomoatic framework provided by the action axiom. Some are held loosely because they apply to our day and age and some are so universal to be considered universal truths in and of themselves, such as the proposition that human beings value leisure to some extent (which can be demonstrated through biology, for instance).
And all of this is not to say that "praxeology is bunk": all of the various implications of an axiom must be true, even if there are other things existing in our reality which are not direct implications of that particular axiom. Simply because one thing is incapable of explaining everything does not mean that the things it does explain are false. And Austrian economics does not limit itself to "pure," axiomatic praxeology. Murray Rothbard, the defender of "extreme apriorism," to use his own term, writes in a footnote of the first chapter of his Man, Economy, and State, that only the first chapter is solely derived from the implications of the action axiom: the remainder of the 1500 page book is dedicated to studying the implications of the subsidiary assumptions that give meaning to the study of economics.
The crucial point is that this is done within an axiomatic framework, and the "empirical" subsidiary assumptions work together with the action axiom instead of against it. They are not "empirical" in the loose sense of the word which is usually used (for example, Okun's "Law" is empirical in the loose sense, yet is entirely unacceptable from the praxeological methodology), and they are constructed in such a way that they apply universally. Okun's "Law" is empirically supported in a way, but it is much more unstable given changes in the day and time and lacks any real sort of "universality" unlike the proposition that people value leisure to some degree. One proposition here is fundamental (leisure) and one is not (Okun's "Law"), and seeing both as "empirical" without distinction is missing the point.
