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Introduction: Science & Knowledge
The primary task of epistemology is to construct a theory that describes knowledge and how it is attained. Epistemology grapples with the nature and nuances of knowledge: its function, its operation, and its boundaries. The systematic pursuit of knowledge and understanding may be deemed science, or, in its more antiquated usage, philosophy. This pursuit must be rooted in an epistemological theory – an understanding of knowledge and the various ways it is acquired.
There are virtually endless fields of scientific inquiry, from meteorology to anatomy, but all of them may be categorized as one of two types. Economics, the primary concern of the present work, is a “social” science, along with fields such as history and sociology. In contrast to the “natural” sciences, like physics and chemistry, social science deals with people’s behavior, interactions, and choices. While both seek to understand and explain certain aspects of reality, social and natural science are categorically distinct from one another. It is only with a coherent epistemological foundation that one can distinguish between the two main types of science, and begin one’s pursuit of systematic knowledge about the world, people, and their interactions.
Ludwig von Mises & Praxeology
During his long career, Ludwig von Mises – the 20th century social scientist and founder of the modern Austrian School of economics – made scholarly breakthroughs which have implications reaching beyond the narrow study of economics. Underlying the Misesian project is a core theory of knowledge and an understanding of choice-making in human behavior. Because this body of thought approaches social science in a unique and novel way, Mises employed the term “praxeology” to describe and distinguish it. Praxeology studies the logical implications of human action, but it also provides more general insights into the nature of science itself. The role that knowledge plays in human action is vital for the Misesian understanding of epistemology and, more particularly, economics. Mises’ theory of knowledge deeply influenced his approach to science – establishing ever-more distinct boundaries between the two branches of scientific inquiry. The epistemological theory offered in the present work will utilize the concepts and terms of praxeology, analyze important distinctions regarding knowledge, and arrive atop a sound edifice from which one can proceed into the sciences. As we will see, the work of Ludwig von Mises has paved the way for much of this analysis.
A Priori vs. A Posteriori
The first task in building a foundation is to determine the difference between “a priori” and “a posteriori” knowledge.1 A priori and a posteriori represent two avenues by which one can attain, or verify, knowledge: by logical deduction and by empirical observation. Attaining a posteriori knowledge requires specific experiences or observational data of some kind, while a priori deductions may occur in the absence of such data. For example, take the claim that no object can be both black all over and white all over at the same time. This can be verified a priori, by deduction alone, because “white all over” and “black all over” are mutually exclusive properties. Due to mutual exclusivity, one may reason that no object can exhibit both properties at once. This is an example of the law of contradiction, which states that no object or entity can exhibit two contradictory properties simultaneously. It is an instance of truth, or knowledge, which can be verified prior to any particular experience – it requires only that one reason through the necessary implications of the concepts in question. On the other hand, knowledge derived through experience, observation, and testing is deemed a posteriori. The fact that water runs downhill, or that oranges contain vitamin C, can only be affirmed by some particular experience. Without the data attained during observation, there is no way to verify or refute an a posteriori truth-claim. In order to find the answers to a posteriori types of questions, it is necessary to conduct tests and make observations, to investigate and gather data.
A priori knowledge, once established, holds true at all times and in all places, like the propositions of logic and arithmetic. A posteriori truths are, instead, hypothetical and tentative, meaning future observations can come along and refute them. In light of stronger evidence, new data, or innovations in measuring capabilities, empirical knowledge can potentially always be overturned with a better explanation. Knowledge acquired from observational data is, in other words, always theoretically falsifiable, or potentially disprovable by new findings.
To avoid confusion, it should be noted that while a priori knowledge can be verified as true through deduction alone, the “building blocks” of our concepts and language are initially attained through the senses, empirically. Once such concepts are learned, however, the possibility arises that they may be employed to discover and establish new propositions that are true a priori. A priori, then, does not refer to knowledge attained before all or any experience whatsoever, but merely to what can be verified as true, logically, in the absence of any particular empirical data. To recognize an a priori truth, it clearly requires prior life experience of some sort, but once grasped it is immediately apparent that such knowledge is true by virtue of logic alone. To illustrate, one must already understand the meaning of the words “black” and “white” before he can determine that it is impossible for an object or entity to exhibit both properties exclusively.
Thus, the avenues to knowledge may be split into two distinct realms: a priori and a posteriori. This important distinction will serve as the basis for a dualist epistemology, or one that demonstrates the fundamentally “dual” nature of knowledge, acquired and verified by two different modes of cognition.
Necessary Truths & Regularity in the Natural Sciences
A priori knowledge is attained by reasoning and reflecting on what is necessarily true. A necessary truth is one that couldn’t possibly be otherwise, like the law of contradiction. To dispute a necessary truth, one must do so on the grounds of logical validity, rather than with data gleaned from empirical observation. This is clearly applicable to basic mathematics. One would only demonstrate their own confusion if they attempted to refute “2+2=4” with some new, cutting-edge data. Austrian economist and rationalist philosopher Hans-Hermann Hoppe provides another example of a necessary, a priori truth:
Whenever two people A and B engage in a voluntary exchange, they must both expect to profit from it. And they must have reverse preference orders for the goods and services’ exchanged so that A values what he receives from B more highly than what he gives to him, and B must evaluate the same things the other way around.2
A posteriori knowledge, in contrast, involves the material world, whose governing laws must be discovered by empirical means. The natural sciences are largely comprised of this type of knowledge. In the study of physics, for example, hypotheses are only affirmed or falsified by data gathered from empirical observation. Scientists study this data and attempt to learn about certain constantly-operating relations of cause and effect: the laws which regulate and “guide” all natural events. Observational science cannot avoid assuming that there are constants in nature, and that due to this regularity, natural phenomena can be understood using data gathered during past observations. In this sense, a posteriori causal laws may be described as “mechanical,” as they are predictable and remain stable over time.
Natural scientists conduct experiments by exposing their object of study to a controlled stimulus, observing, and measuring the resulting response. After repeating a series of tests, the observer hopes to extract from his data some general regularity between causes and effects, allowing him to formulate the trend into an empirical law. Because a posteriori knowledge is dependent upon specific observations and experiences, it is always possible for newly-gathered data to falsify current empirical laws. A theory in the natural sciences holds up only so long as the current data fails to falsify it.
Causal chains may also vary in their degree of constancy. In physics, laws adhere to a strict regularity with virtually no possibility for deviation, whereas a study like biology may only find frequent regularities. Nonetheless, the method of the natural sciences is induction – otherwise known as “causal inference” – where general laws are inferred from a series of tests and observations of the phenomenon in question.3 The laws of physics are especially significant here because every natural phenomenon is subject to them. While the laws of biology or chemistry have their own narrower purview, the laws of physics apply to every natural event. It is this background of regularity that allows the inductive sciences – and everyday experience – to successfully understand the causal relations between various phenomena, and to make accurate predictions concerning the future of such phenomena. The method of induction, then, is fundamentally different in nature from that of logical deduction; they are distinct, separate modes of cognition.
Analytic vs. Synthetic & the Synthetic A Priori
With the a priori/a posteriori division in mind, another important distinction is commonly made in regard to “analytic” and “synthetic” propositions. An analytic claim is one that refers purely to definitions, such as the claim “All bachelors are unmarried.” Even though this statement is true logically, it is entirely a matter of linguistic convention. A claim whose truth depends on nothing more than a definition is also known as a “tautology”. In contrast, a synthetic truth is one that reveals something beyond what may be inferred from the individual definitions of the words used in a claim. For instance, the claim that “Children prefer candy to vegetables” is established as true or false by neither the definitions of “children,” “prefer,” “candy,” etc. It is instead reliant upon additional facts, beyond what can be found in a dictionary.
If a claim is analytic, it doesn’t yield any new information, and refers only to the definitions of the words used in the claim. Since analytic propositions refer only to linguistic conventions, they cannot give new ground on truth or information external to the terms themselves. If a claim is synthetic, on the other hand, it tells us something new, relevant to properties, entities, or concepts beyond the words employed in the claim.
Most, if not all, a posteriori claims are also synthetic, since they always make reference to information external to the terms employed. These are called synthetic a posteriori propositions and again refer to the same kind of empirically-contingent, observational knowledge discussed above. Analytic claims, in distinction, are always provable by a priori means – such as the “bachelors” example – because no additional information is required to verify a tautology. Once one learns the meaning of the word “bachelor,” it is unnecessary for him to go around surveying unmarried men to verify that they are bachelors. Other than the definition itself, no additional information is needed, and so long as the word continues to be used with the same meaning, the analytic claim will remain true, making it verifiable a priori, but no more useful for discovery of new truth.
While these distinctions may appear negligible, the fundamental difference between the two sets of terms – a priori/a posteriori and analytic/synthetic – is that the former deals with whether or not particular experiences are required to verify a claim, while the latter set distinguishes between claims concerning only definitional conventions from those that refer to additional concepts, entities, or properties.
Finally, and most importantly, knowledge can be synthetic (non-tautologous), and, at the same time, a priori (verifiable prior to any particular experience). In the following discussion regarding epistemology and social science, the synthetic a priori will carry great significance. As opposed to empty definitional claims (analytic), or facts attained by empirical observation (a posteriori), the synthetic a priori is an altogether unique, special class of knowledge.
Some of you may be thinking: this is impossible, it must involve a contradiction. How might one attain new, synthetic insights by way of logical deduction alone? Does this imply some sort of infallibility – a capacity to discover new facts about the world solely by power of reason? Initially, it might seem strange, but to fully understand how this type of truth is possible, why it is so important for epistemology, and how it applies to science, exploration into the different types of phenomena is necessary.5
Human Action, Teleology, & “Natural” Phenomena
The two main branches of science investigate two different types of events, or phenomena. Natural science seeks to explain a wide multitude of observable events, from the climate, to chemical reactions, to the biological processes of living beings. Purposeful behavior, or “action,” however, is a unique exception.6 The holistic study of action is instead within the purview of the social sciences.
Action may be described as “teleological” in nature. Action simply refers to that behavior which is conducted in light of one’s conceptual understanding of causal relationships and how they affect the achievement of his ends. Hence, any change in observable reality can be described as either a “natural” phenomenon, or as a teleological one, brought about by an actor who deliberately interferes in the natural course of the world’s events.7
The domain of natural science is primarily made up of synthetic a posteriori knowledge. Physical laws, like gravity, operate on a constant basis of cause and effect, and so are said to be causally-structured. Knowledge about such causal regularities is gained through particular experiences, using the scientific method of induction. Future observations may, again, falsify or disprove conclusions derived from past observations, as induction establishes only hypothetical truths. Though one may repeatedly affirm a hypothesis, he cannot reach ultimate or absolute knowledge through the inductive method of causal inference. Despite induction’s inability to reach absolute certainty regarding particular causal relationships, the principle of causality itself must nonetheless be considered to govern all events that take place in the external, material world. In this context, Mises writes:
… It is impossible for the human mind to think of uncaused change. Man cannot help assuming that every change is caused by a preceding change and causes further change.8
In contrast, the realm of synthetic a priori knowledge is concerned with action. Action can only be understood when a conceptual being (i.e. an actor) reflects on what is logically necessary to his own nature. Here it is especially useful to distinguish action as teleological, or purposeful.9
Teleology is the branch of philosophy which deals with purpose, which is intrinsic to the concept and process of choice-making. When a being makes a conscious choice regarding his behavior, he demonstrates that he values a particular state of affairs over his available alternatives. Choice, then, implies purpose, and since action always involves a choice, it is deemed a purposeful phenomenon. Thus, social science, because it seeks to understand the teleological type of event, must study the acts of purposeful beings – it must study the behavior of actors.10
The spheres of natural and teleological phenomena are distinct, but are also inextricably linked to one another. In the first place, nothing could be said or understood about the natural world without a concept-using, teleological entity there to experience it. At the same time, the existence of action presupposes some external reality in which it can take place. While abstract conceptual thought has no tangible, concrete existence, it is the product of a scarce, material body, subject to nature’s causal laws. Indeed, actors rely on the regularity of such causal laws to successfully reach their goals.
When actors make choices, utilizing their knowledge and preferences, they deliberately implement causes in the world for the sake of creating particular effects. If an actor’s environment did not operate on reliable, causal laws, action would be impossible. An actor could never hope to predict the effects of his behavior based on past experiences, and therefore the achievement of his ends would have to take place without any expectation that one particular cause leads to a particular effect. Without a causally-stable external reality, every behavior would produce new, unique effects, about which no systematic prediction could ever be made. Actors would exist in a perpetual state of random flux, wherein any type of planning or prediction would be impossible. In sum, the world in which action takes place is and must be governed on the basis of cause and effect.
Whether or not action is itself ultimately governed by causal laws is beyond the scope of the present work; however the answer to that question has no effect on the logical truths offered by praxeology. Regardless of what empirical data tells us about action’s ultimate source, actors themselves cannot escape the logical and argumentative necessities imposed on them by their own conceptual nature. Equipped with vital epistemic distinctions between the various types of knowledge, as well as an understanding of how the sciences must apply those types of knowledge to distinct realms of phenomena, we may now explicitly delve into the content of praxeology – a series of inter-connected synthetic a priori axioms.
Praxeology, The Action Axiom, & The Categories of Action
The statement “Man acts” must reside in the realm of synthetic a priori knowledge: it is true by logical necessity, yet it also offers something beyond mere definitions. If one attempts to deny this claim – known as the “action axiom” – he must inevitably affirm it in the course of his denial, because a denial is itself a kind of action. This is known as a performative contradiction. When one demonstrates the validity of a claim in the very act of denying it, the claim becomes axiomatic. One cannot deny an axiom without thereby engaging in self-refutation. Originally formulated by the late economist Ludwig von Mises, the action axiom serves as a synthetic a priori starting point for the entire study of praxeology. In addition to being argumentatively indisputable, axioms can also serve as a foundation from which additional insights may be derived.
Due to the inherent undeniably of this concept, any coherent theory of knowledge is compelled to consider action as its inalienable starting point – any and all discussion of epistemology necessarily takes place within the context of specific actions. Thus, beginning with the action axiom, we may extrapolate the fact that action must involve the use of “means” that are intended to achieve particular “ends”. An actor’s desires or goals are described as his ends, whereas his means consist of the knowledge (particularly knowledge concerning causes and effects), skills, and scarce resources which he uses to reach his ends. For example, if one’s goal is to go to the library, he might decide to use a vehicle, various roads, and his knowledge/ability to drive, all as means to help him get there.
Means and ends are inextricably linked to action, and they directly follow from the action axiom. Every conceivable action can be described or expressed in terms of the end an actor aims at, and the means he employs to accomplish that end. In Kantian fashion, Mises terms the concepts of means and ends as “categories of action,” that is, logically implicit components in the concept of action itself. Because no purposeful conduct could occur without the use of means to achieve ends, they are considered categories of action. The categories are, in other words, “essential elements” of action. Thus, not only is the action axiom itself a synthetic a priori truth, but so are each of the categories derived from it. They are equally indisputable, as their denial, too, must entail self-contradiction. The concepts of value, choice, preference, cost, profit, and loss are also categories of action, each implicit in purposeful behavior and its means-ends framework. Hoppe elaborates further on how these synthetic a priori categories are axiomatic and inherently contained in the action axiom:
For any attempt to disprove the validity of what Mises has reconstructed as implied in the very concept of action [the categories] would have to be aimed at a goal, requiring means, excluding other courses of action, incurring costs, subjecting the actor to the possibility of achieving or not achieving the desired goal and so leading to a profit or a loss. Thus, it is manifestly impossible to ever dispute or falsify the validity of Mises’ insights. In fact, a situation in which the categories of action would cease to have a real existence could itself never be observed or spoken of, since to make an observation and to speak are themselves actions.12 [Emphasis mine]
All of these categories which we know to be the very heart of economics – values, ends, means, choice, preferences, cost, profit and loss – are implied in the axiom of action.13
Elsewhere, Hoppe maintains that the action axiom and its categories are not “self-evident,” or tautologous, and that their elucidation provides us with new, synthetic knowledge, affirmed as true out of logical necessity. This strikes to the very core of what it means for a truth to be both synthetic and a priori. While they may not be, and often are not, explicitly understood immediately, once one is confronted with these insights, he cannot coherently deny them.
Prediction, Observation, & Reflection
The teleological concepts of purpose and choice are not observable to the five senses. Hence, in studying the phenomenon of human action one cannot go forward on empirical data alone. Empirical science studies causal regularities, and this allows for predictions to be made based on past observations. Social science, due to the unique conceptual traits of its object of study, cannot proceed in such a manner. For example, in the natural science of chemistry, predictions can be made about chemical reactions based on observations and tests conducted with certain chemicals in the past. If one tried to apply the same method to the phenomenon of action, he would soon learn that no two individuals respond to external events in precisely the same way. A stimulus – or cause – which provokes a particular response – or effect – from one actor may radically differ for another, due to their unique preferences, values, and knowledge-sets. The same holds true even for a single actor at different instants, as his values and knowledge-sets constantly fluctuate over time. The only conceivable way one could determine the future actions of another would be if action is truly dictated solely by observable causal forces, and if he could take into account all the observable factors affecting this other person. This would include a given actor’s genetic disposition, the configuration of his brain and how it is affected by all types of stimuli, the physical capabilities of his body, his surrounding environment, etc. The observer would then have to understand how this immense set of factors affects each other, and only at this point may he hope to extrapolate a prediction of another’s actions with certainty. This is, of course, currently outside of mankind’s technical abilities. However, whether or not this sort of prediction is even theoretically possible will have no impact on the insights derived from praxeology nor will it in any way affect the epistemic boundaries established by it. A good analogy would be to think of praxeology as providing the formula and empiricism as providing the variables. One requires insights from praxeology in order to meaningfully and coherently interpret empirical economic data, and only through praxeology may incontrovertible economic laws or principles be formulated.
In praxeology, action is not understood using empirical data, but only through a priori reasoning, or “reflection,” on necessary, axiomatic truths (i.e. the axiom of action and its categories). To verify the truths of praxeology, one need not go further than the conclusions generated by his own thoughts, rendering empirical data utterly extraneous. Due to the vantage-point of an actor, he is in a unique position to observe, or reflect on, the concept of action – a position he can never be in while observing any external, natural phenomena. (The existence and specific traits of natural phenomena can only be known through the inductive scientific method.)
Since all of man’s observations are necessarily those of a choice-making actor, one could not attempt any empirical observation of action without already presupposing its existence and the validity of all its categories. Any attempt to observe action is itself an action, guided by value and purpose, using scarce means and aimed at a desired end, taken in place of other alternative actions, and thereby incurring the cost of lost opportunities. One could, therefore, never hope to step outside his status as an actor to observe action in any way at variance with the insights of praxeology. These insights take logical precedence to any observational data, as man’s observations themselves logically must conform to the structure and existence of action in general.
If one does attempt to observe an instance of human action, he will only see an entity moving around in some particular way. Nothing about choice, value, cost, profit, means, or ends will ever be made apparent to the senses of an outside observer. While purpose can be conceptually inferred from observations of an actor’s bodily movement, purpose is itself never actually seen or understood as a result of a mere observation. It is only by reflecting on the logical, conceptual nature of action that one can truly understand it. Thus, no entity but an actor could have access to such information.
A clear example of this sort of reflection can be found in the recognition that every conceivable action is comprised of means intended to achieve ends. This is not apparent to empirical observation, but only deduced from reflecting on the nature of action. It is unnecessary, and indeed impossible, to take measurements and conduct tests in order to prove that actions always make use of means and are aimed at ends. To verify that claim, one needs only to reflect on what it means to act toward a goal (something all actors are necessarily capable of doing).14 This should illustrate the fundamental difference between facts learned through empirical observation, and axiomatic truths attained and verified via reflective reasoning.
Thus, it is confirmed that action is conceptually distinct from all other phenomena. Unlike any other type of event, one can derive logical insights concerning action prior to any specific experiences, while still revealing new, non-tautologous information. This is the fundamental distinction upon which the entire edifice of praxeology is built, and it has serious implications for scientific inquiry in general, and for social science in particular.
The notion of a synthetic a priori truth – once seemingly contradictory – now becomes wholly viable and indeed inescapable when one begins to examine the nature of purposeful behavior. One could not undo the truth of these claims, since actors implicitly demonstrate their validity in any attempt to deny them, as well as in any attempt to observe a situation that did not comport with them.
Knowledge, Truth, & Argumentation
With the idea of purposeful behavior elucidated, the next task is to explore the vital role that knowledge itself plays in action, as well as the roles that language, proposition-making, and truth-validity play in knowledge.
Knowledge is the product of a conceptual mind sorting out sensory data and merging it into an integrated experience, allowing an actor to navigate and understand his environment. Deliberately utilizing means in order to reach goals, or ends, requires the use of knowledge and technical know-how, without which, purposeful behavior would be impossible. Before one engages in action, he must first identify his current situation, determine a more preferable state of affairs, and finally discover how he might reach that condition through his behavior. An actor must figure out the proper changes he is to inflict into the world in order to bring about the desired effects, i.e., in order to reach his end. This process involves “filtering” sensory data through one’s mind to extract the relevant information, with the additional ability to conceptualize, allowing an actor to structure his knowledge in an explicit and concrete way suitable for the realization of his purposes.
Errors, of course, are always possible, and knowledge regarding certain causal chains or facts about the world may not, in reality, hold true. Nevertheless, knowledge – correct or not – is more than just sensory data, but sensory data interpreted and conceptualized by a purposeful, choice-making agent.
The only way to formulate and express conceptual knowledge is by means of language, either verbal or symbolic. Indeed, it is difficult to even imagine conceptual thought totally detached from language, as language gives expressible form to concepts by assigning their meaning to shapes, symbols, and sounds. A language-using entity essentially cannot escape the use of language in formulating his ideas; language is his primary faculty of expression for any knowledge, information, or concept at all. Besides spoken and written language there are also forms of gestural and pictorial communication, but only insofar as such gestures and images can play the same role as words in carrying the meaning of concepts can a truth-claim be expressed in this way.
A truth-claim, or argument, is an affirmation or negation of some facet of reality or some causal relationship. When two language-users reach a disagreement regarding a claim to truth, they are able to engage in argumentative exchange in an attempt to resolve it. Both sides give their own account and each weighs the other’s claims against some standard of validity to reach a conclusion. Argumentation is the necessary result of an actor’s ability to categorize entities and properties into a conceptual framework. Without the ability to organize concepts, not only argumentation, but action itself would become altogether impossible.
It is the expression of one’s concepts using sounds and symbols that other language-users can understand as meaningful. If one tried to deny that language had meaning, he would find himself in a performative contradiction. An objection to any given proposition implies the objector considers his words meaningful, thereby directly contradicting the content of the objection: “language has no meaning”. Since the existence of argumentation is itself argumentatively indisputable, we may also deem it axiomatic. In other words, one cannot reasonably argue that one cannot argue.
It therefore becomes equally impossible for one to deny that he knows the meaning of truth-validity, since in his very act of denial he demonstrates his possession of such knowledge. To dispute any claim whatever, the speaker must appeal to some standard of truth – otherwise, on what grounds could he possibly dispute anything? To support any position, or to undercut the position of an opponent, one must make use of truth-claims in the course of an argument. Hence, that language, argumentation, and truth-validity are genuinely meaningful concepts must already be presupposed if one is to make a case for, or against, anything at all.
The propositions made during an argument, further, are verified or refuted primarily on the basis of logic. In claiming the validity of any proposition, an actor presupposes some objectively-ascertainable standard of truth. If, on the contrary, each person could have his “own truth,” it would be meaningless to argue over the validity of any proposition. Arguments are only meaningful at all when the participants realize that claims to knowledge must be consistent with some basic standard of verifiability, not merely based in their own subjective whims.
Thus, implied in the meaning of truth-validity are, at least, the logical laws of existence (“Something exists”), identity (“Things have distinguishing properties that separate them from all other existing things”), and contradiction (“Because things have particular identities, they cannot exhibit mutually exclusive properties simultaneously” or, more simply, “A cannot be both A and not A at the same time”).
When one says something is true, he means most fundamentally that it is in accord with these basic logical laws. Additional empirical data may be required to verify a particular proposition, but if a claim is directly at variance with a logical law, it can be immediately rejected as false. Logical laws, then, are implied – wrapped up – in the very concept of argumentation.
To illustrate: during argumentation one cannot conceivably avoid assuming that something exists; that is to say, the existence of entities, objects, and matter is indisputable. An argument has to be made by some entity in order to be expressed at all. Also implied in argumentation is the fact that existence is made up of more than just one homogeneous thing; it implies a diversity of entities and properties. Language, and therefore argument, would lose all meaning if there were zero distinctions to be made about anything in reality. To negate or affirm anything using language in the course of an argument, one implicitly assumes a diverse range in the identities of things, to which different concepts and words refer. Finally, related to the presupposition of identity is the fact that objects and entities cannot, at once, exhibit 100% of one property, and 100% of another mutually exclusive property. In other words, contradictions cannot occur in reality, because each extant entity has its own unique set of properties which distinguish it from all other things. No matter how hard one tried, any argument imaginable would implicitly assume the validity of these three logical laws – they underpin the very meaning of truth itself. Again, even if one is ultimately in error regarding a particular truth-claim, to express that claim at all the same presuppositions must still apply.
Similar to the broader concept of action, a necessary component of argumentation is knowledge. The determination of truth-validity and the subsequent use of that knowledge is an essential element to choice-making, regardless of whether or not a particular actor’s conclusions turn out to be actually true. The same holds true for argumentation.
Without at least the faculty to distinguish between truth and falsehood, one could not formulate arguments, nor could he engage in any choice-making behavior at all. As with means and ends, knowledge is a category of action because no specific action could be conceived of that did not contain knowledge as a necessary ingredient. It might be deemed a special type of the “means” category, but knowledge is nonetheless essential to the concept of action.
Furthermore, because knowledge is subject to validity-verification, it serves an active or “positive” function in choice-making. Means and ends are neutral categories, in that all that can be done with them is to simply fill them with the particular content of a given action. Knowledge, on the other hand, is true or false, right or wrong, correct or incorrect. Determining the validity of specific claims is an essential part of how an actor guides his behavior.
Knowledge is only useful insofar as it can provide actors with causally-effective means to achieve their ends. When one acts on incorrect knowledge about the effectiveness of a means, the likelihood that he will actually achieve his end is severely diminished. An actor’s means, ends, and preferences are all determined based on what he knows about his own values, and the current environment in which he is situated. Each actor’s surrounding circumstances will also, in turn, influence his knowledge, preferences and decisions, as different situations offer unique experiences and obstacles to overcome. We may conclude here that the ultimate role of knowledge is to enable actors to succeed in achieving their ends.
The task of epistemology has traditionally been to explore the nature of knowledge. The true function of knowledge, as we have seen, lies with man’s ultimate nature as a choice-maker. Actors use knowledge to navigate between truth and falsehood for the sake of enabling effective action. One may also formulate knowledge into a truth-claim, expressed by language, and such a claim is verified or refuted primarily on the grounds of presupposed logical axioms, and if necessary, empirical data as well.
Epistemology also asks whether there is more than one type of knowledge and, if so, it distinguishes where one ends and the other begins. We have discovered how “action” is the only area of study that can yield synthetic discoveries in an a priori manner. This further illustrates the dualist character of our epistemology – there are only two routes to attain new knowledge: deductive reflection and empirical observation.
Kant, Dualism, & the Empiricists
With praxeological insights at hand, an age-old empiricist objection – that dualism leads to a form of metaphysical idealism – can now be successfully addressed.15
Depending on one’s interpretation, the work of traditional rationalists, like Gottfried Leibniz and Immanuel Kant, seems to imply that external reality must conform to the mind, rather than the other way around. This would clearly entail some sort of idealism, where thought either creates or distorts reality.
In contrast to the empiricist model of the mirror-like mind – inspired by thinkers such as David Hume and John Locke – where all knowledge is derived purely from sensory data, the traditional rationalist model is one of an active mind which meets reality with its own structure of a priori knowledge. This mental structure, Kant believed, was comprised of various “categories of thought”. For example, Kant considered the principle of causality as such a category. He correctly thought that the general existence of cause and effect was not to be observed through the senses, but rather that it was necessarily understood prior to any specific observation. Indeed, as Mises suggests, the human mind cannot even fathom the notion of an observable change in reality that was not the effect of some prior cause. The rationalist accounts for causality by deeming it part of the logical structure of the human mind, rather than something to be seen, heard, or felt. For Kant and Mises, then, the principle of causality is an a priori presupposition, not a falsifiable empirical fact.
In the same way that praxeology uses the term “category” to mean a logically essential element or component, the traditional rationalist notion of categories also consists of truths that are necessary, presupposed ingredients of experience. The principle of causality, while not observable, cannot be detached from any human experience; its existence is presupposed and indisputable. Along with causality, Kant deemed “time” and “space” as categories of thought as well, on the premise that one cannot experience or observe anything without implicitly assuming a general existence of time and space. One could never experience a situation completely devoid of space, nor could any experience take place outside the unrelenting flow of time.
Because raw observational data is nothing more than light photons, sound waves, touch-textures, etc., no part of it is inherently logical or conceptually-structured in any way. Kant’s categories of thought are concepts which help the mind to organize such sense data into something rationally understandable. In other words, a conceptual being does not merely utilize sensory data alone; it is organized by, and integrated with, a priori presuppositions (in Kant’s terms, the categories of thought). This insight strikes at the very meaning of human rationality, a faculty of conceptual understanding which goes beyond mere sensuous stimulation.
The essential rationalist claim is that the human mind must meet observational reality with its own toolbox, so to speak. Kant referred to this as the “manifold of apperception,” where the human mind processes raw sensory input through the categories of thought, resulting in a unified conceptual understanding. In order to coherently grasp the plethora of data with which man is always bombarded, Kant thought that man’s mind must, from the outset, order conscious experience causally, temporally, and spatially.
To this claim, the empiricist might retort that if such an a priori structure of thought was really in place, prior to, or independent of, all experience, in what way could this structure have anything to do with actual, observable existence? If the rationalists were correct, the empiricists charged, this would mean either that the human mind would have to create our reality according to that logical structure, or that the mind distorts reality into something different than what it truly is. In other words, the empiricists argued that the only way for the rationalist to proceed was to adopt some flavor of idealism, where the structure of the human mind distorts reality in order to render it understandable.
However, in light of praxeological theory, we can further elaborate on the notion of an active mind as one that is constrained by the categories of action. With this idea, we can now answer the empiricist’s objection.
Unlike any other phenomena, action is unique in that it simultaneously has a foot in both the teleological realm of thought and the natural realm of existence. One might say that action is the intermediary between the two – where conceptual thought meets observable reality. Indeed, action is the external implementation of internal knowledge and preferences – transforming some aspect of the natural world with the intention of bringing about a more preferable state of affairs.
The categories of action – means, ends, value, choice, knowledge, (the principle of) causality, etc. – are unavoidably valid once the meaning of action is formulated, expressed, and its implications unpacked. Hence, rather than being free-floating figments of the mind with no foundation in reality, as were Kant’s categories of thought, the categories of action are rooted to the very real – and indisputable – concept of purposeful behavior.
We can now see that Kant’s idealistic mental categories become the praxeological categories of action. The difference here is that the praxeological account puts vital emphasis on the notion of action, which has immediate relevance to external reality. The traditional rationalists focused more exclusively on the nature of reason and experience, whereas praxeology seats conceptual thought within its function in action, thereby linking abstract thought to the concrete reality in which action must navigate. On this, Mises comments:
The main deficiency of traditional epistemological attempts is to be seen in their neglect of the praxeological aspects. The epistemologists dealt with thinking as if it were a separate field cut off from other manifestations of human endeavor. They dealt with the problems of logic and mathematics, but they failed to see the practical aspects of thinking.16
Kant’s free-floating categories of time, space, and causality are, instead, directly contained in the action-categories of means and ends. Thus, an end is accomplished only after some means is employed; time necessarily elapses between the two. Furthermore, all action must take place in some physical environment, unavoidably understood by any actor as spatially-structured. Even if reaching one’s end did not involve much bodily movement, all action must take place somewhere in space. At the very least, all action involves the utilization of standing room and the time consumed by the action itself. Causality, finally, is also integral to action, as ends are only reached as the effect of some means; actors deliberately inflict causes into the world in order to reap their effects.
A Realistic Epistemology & Re-Formulating the Categories of Action
Because actions take place in a concrete reality, the action-categories must fundamentally reflect that reality in some way as well. In understanding the role that action plays in our theory, we can bridge from abstract conceptual thought into concrete reality, yielding a very realistic epistemology. As opposed to an untenable idealism that cannot account for the connection between thought and reality, our theory offers precisely that connection. Thus, the traditional rationalists are correct in claiming that certain synthetic truths can be known a priori, but it is only the concept of action that can ground these truths to observable reality and escape all forms of idealism. Since action is guided by thought, yet also affects change into the external world, the categories of action are not only laws of thought, but laws of reality as well.17
Now that we understand how the action-categories are legitimately synthetic a priori, their function in purposeful behavior, and their uniqueness among all other knowledge, we can further derive a complete list of them. We have already explored the categories of means, ends, knowledge, existence, identity, contradiction, causality, space, and time, but we only briefly touched upon the categories of preference, choice, cost/price, profit/loss, and value. All of these concepts are directly deduced from the action axiom: the seemingly basic claim that man acts.
Let us now explicitly demonstrate each category’s inextricable role in action, by way of a hypothetical objection – an attempted denial of the action axiom and each of its categories. In the very act of objection (and, indeed, in any act whatsoever), one must pursue an end to which he attaches value. One aims to accomplish this end by employing some number of means; knowledge necessarily being one of them. Further implied in the concepts of means and ends are the categories of space, time, and causality. In his objection, the speaker must additionally make a choice, setting another course of action aside, thereby incurring the cost of a foregone opportunity. From the costs assumed by choosing one thing in favor of another, the price of each opportunity emerges in respect to the person’s set of preferences. If the speaker accomplishes his end and satisfies his preference (something we know to be impossible, assuming the speaker’s end is to meaningfully refute the concept of action), he can be said to have attained a profit.18 If the end reached by the actor does not satisfy his expectations, to the extent that his costs exceed his benefits, he takes a loss. Finally, all of this must imply an existence in which to take place, comprised of various objects, things, and entities. Each thing exhibits its own unique identity, which rules out the possibility of contradictions.
It is possible that there are additional action-categories, and so while the list may not be exhaustive, it constitutes what can be known about reality a priori. It provides various existential facts that can be deduced, logically, each fact having a direct logical relation to human action.
Due to the way praxeology applies to all actors, the conclusions it yields are universal. They are not unique to social, ethnic, national, psychological, or any other distinction; instead, they apply to each and every acting agent. With an overarching theory that encompasses all purposeful behavior and the knowledge which guides it, we may proceed into the social sciences carrying some vital epistemological assumptions. In the study of economics, we utilize praxeological insights to derive economic laws, which are used to properly interpret the data that reflects purposeful behavior. When analyzing the complex, interwoven patchwork of actions on the scale of an entire society, this methodology becomes indispensable.
Empiricism in the Social Sciences
There are schools of thought that actively seek to refute the existence of such synthetic a priori truths as the action axiom. Two camps emerged in 20th century German academia who opposed the notion of the synthetic a priori: empiricists and, their more radical variant, the Logical Positivists. The empiricists and their more exciting positivist cousins – while supporting the relatively tame epistemology that knowledge is primarily gained through the senses – were very skeptical that anyone could deduce a corpus of epistemological philosophy through a priori axioms.
Such a philosophical foundation would establish the potential legitimacy of science conducted on the basis of a priori truth, rather than by induction alone. It was, in fact, Ludwig von Mises who discovered that social science – and more particularly, economics – could only deal with the logical implications of human action. Working from the typical understanding of his predecessors, Mises revised economic method to fit into the framework of praxeology. Contrary to the popular intellectual fashion of his time, Mises concluded that economics was necessarily a study of action, and could not be based in the traditional Baconian scientific method. In economics, observations can only be interpreted with the aid of an a priori theoretical structure, which is precisely what praxeology provides. If one tried to forego praxeology in an attempt to derive a theory from only observational data, he would run into problems immediately. The conclusions of praxeology are, indeed, inescapable.
The positivist objects to this; he maintains that the only two possible kinds of truth are analytic definitions (tautologies) and tentative empirical hypotheses. This perspective essentially states that certainty cannot be claimed about anything unless it is definitional, which can only involve linguistic conventions. Positivism attempts to introduce a skepticism regarding the human capacity for attaining genuinely absolute knowledge. These academics claimed that the realm of a priori knowledge is exclusively comprised of mere linguistic conventions, representing only arbitrary transformation rules of various symbols (language and/or mathematics) without any scientifically relevant relation to observational reality.
Although the positivists accepted that there is indeed a dichotomy between the realms of a priori and a posteriori knowledge, they postulated that nothing from the former realm could give us any new or meaningful information. To them, a priori truths were virtually free of content in regard to the reality of the world as it exists. Concerning this claim itself, however, one must ask: what kind of truth is that? According to positivist epistemology, the claim that “A priori knowledge can only be tautologous” is either a tautological definition that tells us nothing new, or only a hypothesis, in which case, such a claim may well be falsified in an experiment. Before verifying such a theory, scientists would have to go around “testing” every conceivable proposition to make sure it was in accordance with their epistemological account (that all knowledge is either empty and tautologous or hypothetical and tentative).
If we apply the positivist logic to its own epistemological claim, it is self-refuting. Because the positivists do not regard their own epistemology as tentative and hypothetical – but rather necessarily binding for all knowledge-claims – they must, on pain of contradiction, reject their own methodology. Recall how the positivists want to assert that only two types of knowledge exist: logical relations of the type “All bachelors are unmarried men,” and empirical facts, which can potentially always be falsified by future experiments. When this distinction is applied to the positivist epistemic claim, there can be no solution. According to their own criteria, it must be either logical-tautologous (as in the bachelor example), or empirical; but in either case, they are doomed. For positivists clearly do regard their methodology as helpful and able to offer new information, yet at the same time believe their methodology to be true without requiring any corroborating empirical data to prove it. Contrary to their own position, the positivists must consider their epistemological claim to be non-empirical (because no experiment could falsify it) and also useful because it claims to offer more than a mere definition. The central claim of positivism, then, cannot survive its own distinction. The only way they could ever hope to salvage it would be to concede that it indeed is a synthetic a priori claim, at which point they would have conceded the entire argument, as that is precisely what they were trying to dispute in the first place.
But that is not all – there is a second critique which must be addressed in regard to this school of thought. Sociologists and economists employing a purely empirical method are essentially mimicking the natural sciences, like chemistry or physics. A tentative hypothesis is posited and empirical observation and experimentation are used to affirm or invalidate the proposed theory. Ignoring the obvious objection that there is no sociological or economic laboratory where variables can be steadily controlled, there is an even more fundamental error associated with the attempt to apply the empirical method to any study concerning human action. This error is best illustrated when we analyze the basic assumptions implicit to the empirical method. In absence of such assumptions, empirical science would be either impossible or meaningless. But by incorporating them into our explicit understanding, it soon becomes apparent that no strictly empirical method – free of all a priori assumptions – could ever yield fruitful discovery in the study of action, further demonstrating the vital importance that praxeology has to the field of social science.
If one were to conduct consecutive experiments with the goal of refuting or confirming a proposed theory, it seems one could not consistently commit to the empiricist idea that all non-tautologous knowledge must be empirically-attained. Causes and effects, as Hume famously noted, are themselves nowhere to be seen in observation. But while Hume thought this meant that causality did not itself exist, the truth is that causality is only known through non-empirical, or a priori, means.
If reality were not causally-structured, it would not make sense to say that a past observation could be either confirmed or falsified by any future observation. For example, ask yourself: if observing Experiment A at time T1 is to have any relevance whatsoever to observations made during Experiment B at time T2, what must be true for this relationship to exist? What is to bind these observations to one another, so to speak, and allow a scientist to apply information gathered about past events when making predictions about future events? In other words, why is it not simply that at T1 we see one thing happen and at T2 we see another? Why should there ever be a problem? Why is it true that T2’s results could “falsify” or “confirm” the results from T1? Without the use of any a priori knowledge regarding causality, this question could not be coherently answered. Any given set of observations would have to be seen as simply logically incommensurable with any other set; no hypothesis could ever be tested, confirmed, or refuted. When a scientist derives a theory from his past observations, the only possible way for him to test that theory is with the assumption that future instances of the same phenomena will operate on the basis of the same causal relations. Without this a priori assumption of the principle of causality, the empirical scientist has no coherent or systematic way in which he can test his theories; every new set of observations is completely independent from and irrelevant to the last set.
But it would seem quite ridiculous to deny the acute success of the observational sciences. The astonishing advances in technology and scientific understanding over the 20th century alone clearly demonstrate the practical validity of assuming the existence of a causally-structured reality. The a priori assumption made by empiricists – that physical reality operates on constant and stable relations over time – is not justified under the positivist-empiricist theory of knowledge. Due to the principle of causality, however, scientists are able to make successful and accurate predictions about empirical events based in what they have learned from past observations.
Contrary to empiricist doctrine, then, the principle of causality must be taken to be a meaningful synthetic a priori statement. In fact, no empirical science could be undertaken without this basic, non-observable, non-falsifiable, understanding that causes create effects in constant and predictable ways.19
It is important not to mistake any of the above as an attempt to render the scientific method illegitimate or invalid, quite the contrary. Rather, the question concerns the scope of applicability for the inductive scientific method. The traditional scientific method may still have some limited uses in social science, but the implications of praxeology must be taken as our primary methodological tool. Data in the social sciences can only be interpreted on the basis of a theory, and so theoretical insights are required for a systematic understanding of any kind. In the social sciences, data never speaks for itself, but requires the application of a sound (a priori) theory in order to extract any meaningful conclusions. Praxeology furnishes this theoretical structure.
In regards to predictions, one can say that specific types are inherently untenable. Any prediction that is at variance with the a priori truths derived from the action axiom can be immediately rejected as systematically flawed. For example, one could not reasonably predict that an actor will not employ the first unit of a given set of homogeneous goods toward its currently most-valued end (and the second to its second-most valued end, and so on). The fact that actors employ resources to their most valued ends is part of the economic law of “diminishing marginal utility,” which is derived, a priori, from the action axiom. This all-important axiom, then, serves to confine the logical scope of prediction in the fields of social science.
With the above in mind, it becomes quite clear why a strictly inductive method has no place in a discipline like economics. The mainstream economic orthodoxy constantly makes a variety of impossible predictions using statistics, linear regression techniques, and econometrics. One who takes data about the past and lumps it into a statistical aggregate can only yield a historical account of past economic relations. One can never use such aggregates alone to scientifically forecast future economic phenomena.20 Attempting to do so is akin to Ptolemaic astronomers trying to force math and science to fit their incorrect notion of a geocentric universe. Such an exercise can only result in overly-complicated falsehoods that serve to muddy the waters for future scientific inquiry.
Human action, and the sciences which study it, must be examined with the tools which are attained through reflective contemplation of our own nature as choice-makers. Only the logical ramifications of action can provide tools wholly useful for social science. While the action-categories prohibit one from attaining predictively-helpful causal relations from empirical data, the application of the action-categories does still allow for fruitful analysis, scientific insight, and the use of economic law.
Epistemological dualism allows one to distinguish between the two, categorically distinct, areas of knowledge. The two branches of science which closely correspond with that distinction are also elucidated by this dualism. Economics, history, sociology and the like all involve human action as their primary subject matter, and thus require an entirely different method than that of the physical sciences. The fundamental distinctions made by rationalist philosophy have carved the way for an action-based epistemology; one that recognizes the fundamental difference between a priori-deductive and a posteriori-inductive knowledge. This understanding provides a rock-solid edifice from which an entire science of market exchange can be derived – known as economics, or, as Mises terms it, “catallactics.”
In closing, praxeology offers more than just epistemological truth, but truth regarding the nature of the social sciences and economic methodology. No longer is economics a discipline which aims to ape the methods of the physicist, but one that has its own toolbox to deal with its own unique set of problems and questions. With the conceptual framework of action established, one may move into the realm of economic science well-equipped. It is the concept of purposeful behavior which ultimately grounds our theory of knowledge, and, proceeding into science, it is this action-based epistemological framework which grounds economic theory.
The age-old quarrel between the rationalist and the empiricist frameworks of knowledge can now finally be laid to rest. Whether for physical or social science, one cannot avoid the necessity of employing synthetic a priori knowledge. Rationalism – as espoused by the likes of Immanuel Kant, Ludwig von Mises, and Hans-Hermann Hoppe – has truly validated the human faculty of reason, and man’s capacity to grasp genuine existential truths: truths regarding the marvels of the rational mind, and the universe which it relentlessly endeavors to master.
References and Footnotes
 The approximate literal translations of the Latin terms a priori and a posteriori are “Before the fact,” and “After the fact,” respectively. Also, to avoid confusion, note that in the course of this essay the terms “knowledge,” “claim,” “proposition,” and “truth” will be used to refer to the same concept.
 Hans-Hermann Hoppe, “Praxeology and Economic Science” in Economic Science and the Austrian Method (Auburn: Ludwig Von Mises Institute, 1995). — This quote illustrates the concept of mutually-beneficial exchange, an important idea in the study of economics. It is necessarily true that when two parties trade, each expects to gain from the exchange. If this weren’t the case for both parties, the transaction wouldn’t take place. The very meaning of both parties’ willingness to trade is wrapped up in the fact that each sees more value in what they will receive, as compared to what they’re asked to give up in exchange.
 Induction is commonly known as the “scientific method”: create a hypothesis, test and observe, affirm or falsify the hypothesis, revise if necessary, re-test and repeat.
 As shown earlier, one must already know the meaning of certain words before he can conclude the validity of any claim. Making any proposition will always require some understanding of the terms employed.
 The “analytic a posteriori” type of claim is a subject of controversy, and therefore has been left out of the main discussion. Nonetheless, various thinkers have tried to construct examples of such a truth. An analytic a posteriori truth would have to be attained through experience, yet its meaning would be, at the same time, tautologous. This might relate to how language is learned. That “azule” means “blue” in Spanish is known only a posteriori, yet the claim that “azule is blue” itself is analytic; effectively saying “blue is blue.”
 While humans are currently the only life form we know to live up to the status of “actor,” one should not reject outright the possibility that there exist actors on other planets, or that certain other complex Earth species are also actors. This, however, is the task of zoology, not praxeology. The scope of the present work is to define action and elaborate its implications, not to determine which particular beings happen to be actors.
 Here I refer to the term “nature” only to mean “that which occurs in the absence of any purposeful changes created by an actor.” I do not mean to exclude human beings from the “natural” environment which produced them, and which they are a part of, but only to firmly distinguish the phenomenon of action from all other natural events.
 Ludwig Von Mises, Theory and History (New Haven: Yale University Press, 1957). – It is important to note that it very well may be the case that “action” ultimately operates on the same basis of causality as the rest of the natural world. However, regardless of whether actions are freely taken or causally determined, it retains unique traits which distinguish it from all natural events. No other phenomenon involves the use of conceptual knowledge (particularly the understanding of causal relations) like action does.
 The term “purposeful behavior” is commonly used as synonymous with “rational behavior”. “Rational” in this sense simply means choice-making behavior. In common usage, “rational” refers to someone who makes relatively good choices, whereas in the study praxeology it simply means that a being makes conscious choices (utilizing concepts) at all. Either one of the above terms may be used interchangeably with the term “action”.
 To clarify, any life form that is unable to comprehend the notion of purpose – perhaps by virtue of complete instinct-dominance – is a non-actor. Such organisms are incapable of formulating preferences and conceptual knowledge into plans on which they can act. In contrast to actors, the behavior of this type of being is considered non-teleological, that is, a part of the natural realm of events. Similarly, phenomena like bodily functions or reflexes – even of actors – are not considered actions. An actor has little to no control over certain bodily operations, leaving them outside the realm of teleological, or purposeful, phenomena.
 The notion of the “axiom” itself – as defined in the present work – is fundamentally a praxeological insight. The very meaning of a proposition which one cannot argumentatively deny is tied to the idea that there are presupposed truths which lie behind the concept of “action” (and/or argumentation – see below “Knowledge, Truth, & Argumentation”). It is this which gives axioms their significance. An axiom is considered undeniable only because one must affirm it in his very act of denial. Thus, the only truths which could ever be shown to be axiomatic are ones with some ultimate relation to the concept of action.
 Hoppe, ibid.
 To clarify, it is not the specific content of an actor’s values and ends that can be known a priori, but only the general fact that actors desire the achievement of ends at all. One could not deny this without implicitly affirming its truth, as again, any denial would involve the use of means intended to achieve an end, and would thereby constitute an action itself.
 “Idealism” in this context simply means that the objects of physical existence are somehow reliant upon, or created by, the mind.
 Ludwig von Mises, “Some Preliminary Observations Concerning Praxeology,” in The Ultimate Foundation of Economic Science (New York: Van Nostrand LTD., 1962), 2.
 This serves to reconcile the small quarrel between Ludwig von Mises and Murray N. Rothbard, two giants in the field of praxeology. The latter maintained that praxeology furnished existential laws, whereas Mises held that they are epistemological laws. We can now see that they are both. This reconciliation opens the possibility for an action-based theory of metaphysics, but that will have to be the subject of another essay.
 Note that “profit” does not necessarily mean monetary profit, as the term is commonly understood. An actor may profit only mentally, or psychologically, but in the context of praxeology, it is profit nonetheless.
 To quickly address the possible objection that certain aspects of quantum physics somehow disprove the idea of a stably-structured reality, one can only answer: as far as praxeology is concerned, quantum states and infinitesimally small measurements of time and space are not relevant for actors. Action is always concerned with the marginal – not the quantum – level. Man is not able to act on the basis of such inconceivably small distinctions, but only those which he can actually detect. Quantum physics may well upset or shake up conventional notions of causality, but so long as the discussion is focused on human action, we have no reason to assume that the principle of causality is invalid. On the contrary, action per se implies that actors recognize their actions as demonstrably affecting their natural surroundings on the basis of cause and effect. Quantum physics could not refute the fact that there is a significant degree of stability in the world in which man acts, and that, in acting, he implements and observes definite causes to reap (and, in the case of science, study) their effects.
 It is important to distinguish systematic scientific prediction from the type of forecasting that entrepreneurs commonly employ in the market. Entrepreneurs discover or follow trends in an attempt to anticipate the desires of other actors; however they are useless, by themselves, in formulating a scientific “law.” Such trends can yield no information regarding causal relationships, but merely illustrate facts about historical trends and events.