

Other creatures with different fundamental physical natures – including plants and the lower animals – lack the capacity to act, since they lack volition: their existence is sustained by instinct and reflex. The acting man sees that these creatures are fundamentally different from him in body and mind and therefore concludes that they cannot act. However, all humans share the same fundamental physical nature: their bodies exhibit a similar appearance – all particulars of bodily dimensions, color, gender, and miscellaneous small details notwithstanding. Furthermore, the essential physical structures of every man's brain and sense organs are the same. An acting man encountering any other man will realize: "This man fulfills my previously arrived at criterion for acting beings – since he is fundamentally similar to me in his characteristics, and I know that I am an acting being."



The universality of action among human beings is no mere hypothesis: it is a fact knowable with certainty. Just because we can only discover the existence of action by looking into our own minds does not mean that action is a product of our imagination, severed from reality. On the contrary, "our mind is one of acting persons. Our mental categories have to be understood as ultimately grounded in categories of action. And as soon as this is recognized, all idealistic suggestions immediately disappear" (Hoppe, "Praxeology and Economic Science: Sec. I"). The existence of our actions in reality is the very reason why we can introspect to discover the fact that we act. Implicit in action is the pursuit of ends via real means: even if the ends the actor pursues are in fact non-existent – such as the favor of the great Rain Spirit in watering his crops – his means toward pursuing that end must exist in this reality. If he does a rain dance to obtain the fictitious spirit's favor, he will be dancing with a real, physical body upon real ground, asking the Spirit to pour water on real crops.



If a man acts, he must necessarily be linked to reality and able to pursue real means – otherwise, he would not be able to act. Man understands the real nature of his actions through the use of his mind – through introspection. In fact, introspection is itself an action, as are all the fundamental processes of man's mind: as "categories of action, they must be mental things as much as they are characteristics of reality. For it is through actions that the mind and reality make contact" (Hoppe, "Praxeology and Economic Science: Sec. I"). Action can be manifested in external reality, but it requires the mind to grasp. It cannot be solely a mental category detached from the outside world – since it is the prerequisite for and determinant of all human mental categories. Nor can action be a solely empirical category distinct from the operations of the individual actor's mind, since the mind – aside from being necessary for introspection – assigns to acting man his choice of ends and means. Action can be grasped by neither reason nor observation alone; in bridging the two, however, it affirms the validity of both. Since man's mind belongs to a being acting in reality, its analytical faculty – its reason – can accurately interpret human observation – or the data of reality as available to the human senses. Moreover, since every man is an acting being – every man has the capacity to reason accurately and make accurate observations, if he chooses to use that capacity.

Certain Knowledge Since, following from the action axiom, man's reason can accurately interpret his observations, it can thereby obtain fully correct, certain knowledge about aspects of reality. The science of praxeology consists of a systematic collection of certain knowledge derived from the action axiom and known to be true. Just as the action axiom is irrefutable, so are the propositions stemming from it. Man can know the truth of praxeological propositions fully and absolutely: no amount of further experimentation or empirical evidence can refute them.

Its statements and propositions are not derived from experience. They are, like those of logic and mathematics, a priori. They are not subject to verification and falsification on the ground of experience and facts. They are both logically and temporally antecedent to any comprehension of historical facts. They are a necessary requirement of any intellectual grasp of historical events. (HA, p. 32) Praxeology offers synthetic a priori insights about reality. It requires no observation to arrive at, but nonetheless offers knowledge that no observation can possibly refute – and many observations will confirm. Furthermore, praxeology is synthetic a priori true, because its starting point – the action axiom – is irrefutably correct. Praxeology is not merely analytic a priori, since it requires more than the mechanisms of formal logic to confirm: one has to be an acting being oneself in order to know of action and praxeology. While formal logic is necessary in explicating praxeology, it is not sufficient: logic is a category of action and must be preceded by it. Axioms – like the proposition that humans act – cannot be proved by means of logic alone. They are the starting points of logical systems and thus cannot be arrived at from within the systems themselves. Their truth is known more fundamentally: any attempt to refute them implicitly confirms them.



The action axiom makes possible the acquisition of a plethora of a priori knowledge about reality. A priori true economic propositions, however, are arrived at with especial directness: "Economic propositions flow directly from our reflectively gained knowledge of action; and the status of these propositions as a priori true statements about something real is derived from our understanding of what Mises terms 'the axiom of action'" (Hoppe, "Praxeology and Economic Science: Sec. I"). Economics, as a subcategory of praxeology, is rationally knowable not merely because of the action axiom, but as a direct derivation from it. For example, the law of diminishing marginal utility can be deduced from the action axiom. In acting, a man uses a given economic good to fulfill a set of available ends. If he values a given end above all others, he will devote his first unit of the relevant good to that end – since his valuation of that end can only be observed via the actions he takes to pursue it. He will necessarily devote his second unit of the same good to the second most subjectively valued end he deems attainable via that good's use. The value the actor derives from the use of the good's second unit is thus necessarily less than the value obtained from using its first unit: the second most valuable end is necessarily less valuable than the first. Such reasoning can be extrapolated indefinitely, applicable to as many units of a good a given economic actor might have, no matter what the identity of the actor and of the good in question might be. The law of diminishing marginal utility holds for all time periods – past, present, and future – and no empirical datum could conceivably refute it.



But the propositions of economics are not the sole extent of a priori knowledge made possible by the action axiom's existence. Indeed, to clearly delineate the bounds of knowledge that can be arrived at via an axiomatic-deductive approach, another a priori truth is needed: "that humans are capable of argumentation and hence know the meaning of truth and validity" (Hoppe, "On Praxeology and the Praxeological Foundations of Epistemology: Sec. III"). Hoppe's axiom of argumentation, like the action axiom, cannot be consistently denied. One's attempted refutation of the existence of human argumentation would itself be an argument.



Metaphysically, argumentation is a subclass of action: to argue is to select a set of verbal and logical means to pursue the end of demonstrating something to be true or false. However, epistemologically, argumentation is prior to action: "without argumentation nothing could be said to be known about action" (Hoppe, "On Praxeology and the Praxeological Foundations of Epistemology: Sec. III"). The only way one can use argumentation is if one is an acting being. However, the only way one knows that one is an acting being is by using his reason and exercising argumentation. If one did not use argumentation (including abstaining from attempting to deny one's argumentative capacity), one would never know that one is an acting being – nor would one be able to articulate to himself or others why one pursued a given course of action. One would have to choose ends and means without knowing why one chose them. This is a contradiction in terms: the very concept of ends and means makes no sense without the actor's exercise of reason. Saying or thinking, "I chose means X to get end Y," constitutes an argument and a reason for one's action. Without the ability to convey this reason to at least oneself, one would not be able to act at all. The capacity to act implies the capacity to use argumentation.



Only through argumentation can one arrive at the action axiom and the praxeological knowledge following from it. But because argumentation is, in fact, based on action, it can arrive at certain truths: "the possibility of argumentation presupposes action in that validity claims can only be explicitly discussed in the course of an argumentation if the individuals doing so already know what it means to act and to have knowledge implied in action" (Hoppe, "On Praxeology and the Praxeological Foundations of Epistemology: Sec. III"). Since we are beings who act in reality, our argumentation – being a type of action – is also in and of reality.



It is possible to argue falsely: this would be a specific case of using improper means to achieve a desired end. However, correct argumentation is similarly possible, as is a more general case of using means that actually fulfill a given actor's goals. If it were impossible to act correctly, then no means selected by humans would ever arrive at ends those human beings aimed at. Since we observe ubiquitously that human beings frequently select proper means to actually fulfill their ends, we know that a correct pairing of means and ends is possible. Since argumentation facilitates the pairing of means and ends, correct argumentation must be possible as well. If correct argumentation were impossible, so would any sort of eradication of dissatisfaction – which can only come about from reaching one's chosen ends. Furthermore, if no human ends – including basic survival needs – were met, all humans would be long dead. We know that many humans exist and routinely remedy dissatisfactions; therefore, much of their action and argumentation must be correct.



Since argumentation pertains to reality, man can obtain knowledge about reality by using argumentation correctly. Knowledge, the product of argumentation, is then itself a category of action.



If argumentation is a subclass of action, then the realm of a priori, certain knowledge can be described as the realm of propositions that can be arrived at argumentatively, without being contingent on any additional external observations. According to Hoppe, the "task of epistemology [is] that of formulating those propositions which are argumentatively indisputable in that their truth is already implied in the very fact of making one's argument and so cannot be denied argumentatively" (Hoppe, "On Praxeology and the Praxeological Foundations of Epistemology: Sec. III"). According to Hoppe, epistemology must then "delineate the range of such a priori knowledge from the realm of propositions whose validity cannot be established in this way but require additional, contingent information for their validation, or that cannot be validated at all and so are mere metaphysical statements in the pejorative sense of the term metaphysical." Proper epistemology will tell us which facts can be known through reasoning and introspection – and which require specific observations to verify; furthermore, it will tell us which propositions are absurd or altogether irrelevant to reality. The action axiom enables such an epistemology to claim that man can be certain in the accuracy of both his a priori knowledge and his observation – that no fact of reality is inherently off limits to human comprehension.



Any denial of knowledge inextricably linked to the axioms of action and argumentation would entail a contradiction of one's own argument and would be refuted by one's very ability to argue. Furthermore, the realm of a priori knowledge is praxeologically constrained: it is only as broad as the categories of human action allow it to be. It is possible to have genuine a priori knowledge about something other than action, but the very pursuit knowledge can only be facilitated by action. Knowing is an end toward which deliberate physical and mental activity is a means. This praxeological constraint is in fact an assurance: it allows us to understand all genuine a priori knowledge as knowledge of reality, and not merely of the categories of our own minds. Hoppe explains: "Acting is a cognitively guided adjustment of a physical body in physical reality. And thus, there can be no doubt that a priori knowledge, conceived of as an insight into the structural constraints imposed on knowledge qua knowledge of actors, must indeed correspond to the nature of things" ("On Praxeology and the Praxeological Foundations of Epistemology: Sec. III"). Because action necessarily exists in physical reality, a priori knowledge – being a subcategory of action – must also pertain to that reality. Action and, in particular, argumentation provide a figurative bridge through which the data of reality can enter our minds and reside there without being vulnerable to further disproof or rejection.



The ability to arrive at certain a priori knowledge about reality deals a mortal blow to two doctrines denying the possibility of accurate axiomatic-deductive theoretical insights: empiricism and historicism.



Part Two >>