Is the praxeological method a valid approach to discovering economic truths?

Welcome to the debate arena! Today's topic: "Is the praxeological method a valid approach to discovering economic truths?". Your opponent's style: Any neoclassical/orthodox economist.

I believe the praxeological method, famously developed & used by Misesian Austrian economists, is a valid method of deducing economic truths. Praxeology starts from the axiom that man acts, with action defined as purposeful behaviour as opposed to instinct, reflex &c. We know that man acts because to doubt that man acts is itself an action made by a person with an end, which uses means & results in income & cost for the person. Human action is incontrovertible because its denial is its admission. Therefore, it is a synthetic a priori proposition; synthetic because action is not included in the definition of human but nevertheless is necessarily derived from humanity, a priori because no sensation or empirics are necessary to establish its validity. From the axiom of human action, we can derive more a priori truths from the axiom to apply to real world scenarios. For example, we know that for an action to take place, that action will have an end, a goal that the actor wants satisfied. In order to attain this goal, the actor must believe that by intervention in his environment, his end is attainable. From then, the actor utilises scarce means, including his body, in order to enact the intervention he believed would cause his end to occur. At this point, either the end was attained, resulting in a psychic profit, or the end was not attained (or attained with massive costs), in which case there is a psychic loss. If all ends were ranked equally desireable, then no action would take place from anxiety over what to do. Therefore, all ends are ranked ordinally from most desired to least desired & are constantly changing. Therefore, cost involves all of the ends made impossible to attain by choosing the most highly valued end. If it turns out that the end the actor had in mind isn't successfully reached, then the cost of foregoing other ends outweighs the benefits of using the scarce means to reach the end. If the end is attained, then subjective ordinal ranking of ends means that the actor must have profited. This also reveals that every identical unit of a good --- a scarce mean --- must fulfill the next most highly valued end that an actor has. If the first unit goes to the most highly valued end & the next unit goes to the next most highly valued end, the subjective marginal utility in each unit decreases & decreases until the amount of units of a good surpasses the ends that could possibly be achieved & all further units are worth nothing or potentially harmful due to space taken up &c. This is the law of diminishing marginal utility. Several other examples of truly a priori concepts can be brought up, but that is not all praxeology is able to enlighten us about. Praxeology can be applied to real-world empirical examples as necessary derivations of the essence of action itself. Take for example, the proposition that in every exchange, each party in the exchange must value the good they are receiving more highly than the good they are offering, otherwise the exchange wouldn't happen. Or perhaps the law of association, where people who have different skills & goods are able to cooperate & trade to produce the goods most efficiently, benefiting each other even while focusing selfishly on bettering their own situations. Therefore, the praxeological method of deducing economic truths from the action axiom & applying them to real-world economics is valid & useful.

You're smuggling empirical claims into what you call pure logic. The axiom "man acts" might be unfalsifiable, but everything downstream requires the world to cooperate with your deductions. You claim diminishing marginal utility follows necessarily from the action axiom, but that's false—someone might value the hundredth dollar exactly as much as the first if they're desperate. Your system can't account for this without peeking at reality. You've built an elegant cage and called it truth-discovery, when really you're just assuming the conclusions you want.

1. If the action axiom is unfalsifiable, everything downstream is unfalsifiable unless there are falsifiable assumptions put in. The only further assumptions made are scarcity (which is unfalsifiable because denying it would assume that one is an infinite God whose body & mind are non-scarce means) & existence (which is unfalsifiable because you need to exist to act). All of these are preconditions to action & therefore must be implied by the action axiom, meaning they are a priori. These a priori truths are the very structure of human action itself so the world cooperating is a given which one does not need to be worried about. 2. For someone to value the hundredth dollar just as much as the first dollar one of the following propositions must be true, neither of which invalidates the law of diminishing marginal utility as a priori true: a) he values every dollar extremely closely to the last dollar & it just seems like they have the same utility even though they satisfy just a slightly less valued goal each time; b) this is taking place over time & he gains new & previously unknown ends satisfiable by each new dollar as the previous end is fulfilled by the previous dollar (in which case the ranking of ends just is barely applicable because each new end is exactly as valued as the end immediately satisfied before, meaning these are substantively different value scales); or c) the unit in question is not one dollar but one-hundred dollars.

You're playing shell games with unfalsifiability. Yes, scarcity is "unfalsifiable"—so is "invisible unicorns govern markets." Unfalsifiable doesn't mean true, it means untestable. Your law of diminishing marginal utility dissolves the moment you admit option (b): if new ends emerge constantly, you're not deducing from action—you're smuggling in empirical psychology about how humans form preferences. That's observation, not a priori logic. You've dressed empiricism in a priori clothing and called it deduction. What makes you confident your system captures how humans actually rank ends?

1. I've already explained how the action axiom is incontrovertibly true & therefore how scarcity is true. Using your language is not stating that unfalsifiability implies truth. "Invisible unicorns govern markets" is not true in the same way as the action axiom because there is no way to deduce the existence of invisible unicorns from a priori principles. 2. Time is known a priori because there is always a logical order to thought & action & because of scarcity logical order implies temporal order. Praxeology is explicitly not psychology --- psychology deals with ends in & of themselves & the mental states leading up to action, praxeology deals with the actions in & of themselves --- so we always work from the existence of value scales --- implied by action --- & the existence of scarce means & units of goods. If value scales exist then each identical unit of a good must satisfy the next highest valued end. Saying that value scales can change across time is not admitting empirics into praxeology. Your question does not attack the law of diminishing marginal utility if the situation must rely on a completely different value scale being formulated as each new dollar pours in & adding in the existence of temporal order changes nothing about that. Again, praxeology does not deal with how ends are formed, only with *that* ends are formed & how actors achieve each end. Me choosing to use scarce means to debate you implies that I rank the expected psychic income I would gain from having my beliefs vindicated --- by convincing you --- over every other end on my value scales. Value scales do not change unless new information is gained & all action occurs starting from information which supplies the ends. Your rebuttal to the law of diminishing marginal utility relies on comparing two completely substantively different scenarios in which an end is achieved using a unit of a scarce mean & asking me to explain why something different is happening.

You're confusing logical consistency with truth-discovery. Yes, your axioms are internally coherent—that's what makes them useless. A perfectly self-contained system that excludes empirics can't tell us anything about actual economies. You say praxeology ignores psychology, but value scales ARE psychology. You can't wave away how preferences form and claim you're still making truth-claims about real human behavior. Your system works only if humans behave exactly as your axioms require. What happens when they don't?

The process of gaining information is empirical, but that does not change anything about praxeology. Praxeology provides the a priori insights necessary to understand the actions people take according to the information they have. It isn't possible to know what someone values a priori, but it is possible to know about value scale from the action axiom. It isn't possible to know what information someone might gain in the coming seconds a priori, but it is possible to know that new information can change what ends they value highest. Your rebuttal to praxeology relies on assuming it functions beyond its scope. Praxeology is not about knowing everything from the dawn of man to now a priori, which is what your rebuttal requires, it is about understanding the necessary structures of human action & what they imply for economics & economic theory. You claim that value scales are psychology, which is 100% true. What ends I rank most highly is a psychological concept & is responsive to empirical information gained. However, knowing someone's value scales is not the goal of praxeology, rather, the other way around is. The goal of praxeology is not to deduce what ends people value from what actions they take but to deduce what action is & how it responds to the ends people may value. Toy models are useful but not concessions of the usage of empirics in praxeology. Empirics are useful in diagnosing what's going on in the real world, but unnecessary for deducing the a priori structures which allow us to truly understand human action. With these insights into human action, we know certain conclusions can be mapped onto the observable world. The "axioms" you refer to are actually one incontrovertibly true axiom --- man acts --- & all the truths which are deduced from that axiom. Again, the axiom's status as true provides the status of all conclusions also true. There is no worry that people won't behave that way because to claim people will is a total self-contradiction. Trying to sneak psychological claims in to try invalidate the axiom altogether is missing the point entirely.

You've retreated to unfalsifiability and called it strength. "Praxeology describes structures, not predictions"—fine, then it's philosophy, not economics. Real economics must tell us what actually happens. Your system works because you've defined failure away: humans always act according to your axioms because you redefined "action" to fit them. But that's circular reasoning dressed as deduction. If praxeology can't be wrong, it can't tell us anything about the world. Why should policymakers care about a system that explains everything and predicts nothing?

I never said that praxeology cannot make predictions. As a matter of fact, Austrian economists have use praxeology to predict economic recessions such as the 2008 housing market crash while other economists brushed concerns aside. I've not defined failure away, I've explained how human action is undeniable & what results from that. The essence of human action can absolutely be used to describe what goes on in markets & even potentially make predictions about what will happen. However, those predictions are about what happens when markets are interfered with, when human action is interrupted. Friedrich Hayek spend years trying to explain to people that the economy is not something you can look at in isolation & make predictions & policy decisions about.

Austrian economists predicted the 2008 crash, sure—but they've predicted twelve of the last three recessions. Cherry-picking hits while ignoring misses isn't validation, it's confirmation bias. And your defense reveals the real problem: praxeology only "works" when markets are interfered with. That's unfalsifiable by design. When predictions fail, you blame external factors. When they hit, praxeology gets credit. You've built a system where you win either way. How is that different from unfalsifiable pseudoscience?

I have said nothing of what you claimed I have. Praxeology works full stop. Any man who claims that he can predict what will happen in the economy completely ignores the fact the new knowledge is gained by people every single day. Your quip about predicting twelve of the last three recessions is usually used to described non-praxeological economists who think their mathematical models can substitute for true knowledge on how & why humans act. Praxeology is able to predict what will happen when markets are interfered with by using "toy models" as illustrations. The best example is the evenly rotating economy, which is a model used to demonstrate what will happen to an economy in equilibrium when its functions are disrupted by external forces. However, we cannot predict what the economy --- or more accurately, the people --- will do. We do not know what information will be gained tomorrow, what supply line crash will send ripples through prices in the economy, what people's value-scales are. This is why the economy is so important, it transmits information more efficiently than any other method about how resources should be allocated. What is great about praxeology is that it gives us insight into how people behave in markets & what has caused certain market phenomena. I'd like to point out that your demand for some popperian falsifiable empirical metric is completely out of place & unscientific. Falsifiability is important in the natural sciences because "what will happen when chemical a is mixed with chemical b" is not something knowable a priori the same way the action axiom is. In truth, it's not that praxeology "can't be wrong", it's that it baldly isn't wrong. We've not redefined action to be undeniable, it just is undeniable without performative contradiction. Economic pseudoscience is not some quack making false claims about physics the same way, say, chemical pseudoscience is. Economic pseudoscience is the misapplication of scientific methods to philosophical inquiries. The a priori synthetic nature of action qua action & all the truths derived from the axiom of action means that testing is unnecessary. To claim that economic truths require extensive "scientific" testing would be similar to claiming we need to make study after study in multiple continents to prove the hypothesis that "a ball cannot be both red & blue all over."

You've just admitted praxeology can't predict anything specific—only explain everything after the fact. That's not insight, that's storytelling. You compare economic action to "a ball can't be red and blue"—but reality is messier. People act irrationally, emotions override logic, information cascades create chaos praxeology can't touch. Your system works beautifully in isolation because you've removed all the friction that makes economics hard. When markets crash unexpectedly, you blame "external forces." That's not unfalsifiability making you rigorous—it's making you useless to anyone trying to understand what actually happens.