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Study Guide to Human Action, Chapter II

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Tags Austrian Economics Overview

07/06/2007Robert P. Murphy

[This Study Guide to Human Action, Chapter II is also available in PDF.]



1. Praxeology and History

Praxeology and history are the two main branches of the sciences of human action. History is the collection and systematic arrangement of all data of experience concerning human action. The natural sciences too deal with past events, but their successful use of induction relies on the experience of past experiments. In contrast, in the sciences of human action there can be no controlled experiment, and hence a different method is needed. Praxeology starts from the fact of human action and uses logical deduction to arrive at a priori truths which are valid for all action, both in the past and future.

2. The Formal and Aprioristic Character of Praxeology

The logical structure of the human mind is an unanalyzable given. One cannot "prove" logical relations because such a proof itself would rely on logic. The principles of causality (cause and effect) and teleology (i.e., understanding certain events by ascribing conscious motivations) are also necessary prerequisites for the mind to make sense of the world.

The Alleged Logical Heterogeneity of Primitive Man

Certain anthropologists believe that the members of primitive tribes possess "prelogical" minds. This confuses the content of their minds with the logical structure. People who do a rain dance are still adopting means to achieve an end; it is simply that they have different technological beliefs from Westerners.

3. The A Priori and Reality

Even though praxeology's claims are a priori, they still "teach us" something about reality. Geometrical or mathematical theorems are also "mere" transformations of the initial premises or axioms, yet mathematicians certainly add to human knowledge and allow people to achieve more in the real world.

Far from relying on past experience to generalize and reach a tentative theory of economics, when it comes to human action we can only interpret past exchanges, costs, and so forth with an antecedent knowledge of praxeology. Without knowing beforehand about action, we would only perceive bodily motions, not buying and selling.

4. The Principle of Methodological Individualism

Praxeology concerns the actions of individuals. It is true that people may behave differently when they view themselves as members of a nation, or when in the midst of an unruly mob. Even so, the "nation" does not bomb another country; individuals in the armed forces choose to obey such orders.

I and We

The collectivist mindset is apparent when people refer to "we" when in fact such individuals had nothing to do with the actions in question. If a US citizen says, "We won World War I" this of course is literally false. There is no such confusion in the term "I."

5. The Principle of Methodological Singularism

Praxeology deals with individual actions, not vague action in general. Those who think in terms of universals fall into traps such as the classical water-diamond paradox: Why is the price of diamonds higher than the price of water, when the latter is more important?

6. The Individual and Changing Features of Human Action

Although the "common man" doesn't "think for himself," he still chooses to act in the traditional way. If someone votes Republican because her father did, she is still acting in the praxeological sense.

7. The Scope and the Specific Method of History

The historian can't simply let the facts speak for themselves, because this would lead to a cacophony. Rather he must use his prior value judgments and theories to determine what is relevant and then present the facts accordingly.

The historian can and must rely on the knowledge of other disciplines. But when praxeology, physics, mathematics, etc. cannot contribute anything else to the interpretation of an historical event, the historian relies on understanding, which is his unique contribution.

8. Conception and Understanding

The task of the sciences of human action is the comprehension of the meaning and relevance of human action. Conception is the tool of praxeology, while understanding is the tool of history.

Natural History and Human History

The natural sciences too deal with historical events, especially in the fields of cosmology and geology. However they still rely exclusively on the methods of the natural sciences and do not involve understanding.

9. On Ideal Types

The historian relies on ideal types that represent his judgments of relevance. Unlike the concepts of praxeology or even the natural sciences, ideal types cannot be described by necessary and sufficient attributes. What economic theory says about "the entrepreneur" is valid for all entrepreneurs, but the historian's use of the term may apply only to a particular period or people.

10. The Procedure of Economics

Economics proceeds with logical deductions from the fact of action. It can study special cases of action by considering specific conditions in which action could occur (for example, if there is a universally accepted medium of exchange).

It would be possible to study the implications of human action in worlds that are utterly different from our own. For example praxeology could consider the case where labor yields no disutility. Yet the end of science is to know reality, and so praxeology restricts its inquiries to those cases where the preconditions could be achieved in the real world. Even so these deductions are completely a priori. We use our experience to sift out the relevant from the irrelevant chains of thought; we do not use our experience to determine the validity of a particular chain of reasoning.

11. The Limitations on Praxeological Concepts

Praxeology only makes sense when applied to acting human beings. It breaks down into paradox with a being such as the Christian God. Action implies uneasiness, yet an omnipotent being would in one fell swoop achieve perfect contentment.


Epistemology seeks to answer the question, "How can we ever 'know' something?" In this chapter Mises establishes the epistemological foundations of praxeology, that is, he explains how it is that economists and other social sciences can arrive at beliefs concerning actors and have confidence in their conclusions.

Especially as the 20th century progressed, most economists thought that they needed to ape the method of the physicists to arrive at "scientific" laws in their field. Mises's insistence that praxeology's propositions were "a priori" thus struck them as shocking and quaint.

If a statement is a priori, its truth can be established without external observations. For example, we can verify the Pythagorean theorem without measuring triangles to "test" the claim. On the other hand, if a statement is a posteriori, then logic alone cannot verify or refute it. For example, if someone says "the sun emits heat," then sensory observation is necessary to evaluate the claim.


(1) Mises's taxonomy is a bit confusing. On page 12, he had defined praxeology as the general theory of human action. Yet in the present chapter on page 30, he refers to praxeology as simply one branch in the "sciences of human action."

(2) Mises claims that the natural sciences advance because of their reliance on experiments, which "can be used for induction, a peculiar procedure of inference which has given pragmatic evidence of its expediency, although its satisfactory epistemological characterization is still an unsolved problem" (p. 31). All Mises means here is that philosophers at least since David Hume have noted that there is actually a fallacy involved in the method of the natural sciences. Simply because X led to Y 35 times in a row in the laboratory, does not logically imply that X causes Y. Even so, no one can deny that the experimental method has "worked" in the natural sciences.

(3) Mises distinguishes between a priori and a posteriori statements (see Why It Matters above). Hans Hoppe introduces yet another distinction, between analytic and synthetic statements. (Analytic can be determined simply by analyzing the components of the proposition — e.g., "A bachelor is an unmarried male" — while synthetic statements add to our knowledge; they refer to the "real world" and are not merely definitional.) Hoppe argues that Mises's grand achievement was to prove the existence of true, synthetic a priori propositions — something that Hume and other philosophers considered impossible.

Though a fascinating extension of the Misesian framework, it is interesting to note that in Human Action Mises himself never discusses the analytic/synthetic dichotomy.


1. Praxeology and History

What are the two main branches of the sciences of human action?

What is the field of research of history? Can it tell us something about the future? Why or why not?

Is it possible to establish an a posteriori theory of human action with the aid of historical knowledge?

Praxeology is an a priori science. What does a priori mean in this context?

2. The Formal and Aprioristic Character of Praxeology

Mises states that the fundamental logical relations are not subject to proof or disproof.


What does he mean by methodological apriorism?

Why is it fallacious to pretend that the logical structure of mind of primitive man is different from that of civilized man?

Does exorcism represent a sort of action? Why?

Does action imply that it attains the end aimed at?

3. The A Priori and Reality

Can aprioristic reasoning enlarge our knowledge? Why not? Give an example.

Why do the sciences of human action differ radically from natural sciences?

Why is praxeology inevitable in order to discern human action?

Why can't history teach us any general rule, principle or law?

4. The Principle of Methodological Individualism

Can a collective whole act? Why not?

Why is it necessary to examine collective wholes through an analysis of individuals' actions?

Why will the acting and choosing being always be an Ego?

5. The Principle of Methodological Singularism

What does the act of choosing always imply?

What are the two aspects of every action?

6. The Individual and Changing Features of Human Action

In what way does inheritance and environment direct a man's action?

How does praxeology deal with routine? Is it due to conscious acting and to a deliberate choice?

7. The Scope and the Specific Method of History

Why isn't it feasible to present history without any value judgments?

What is always the "genuine" problem of historians?

Why is history unsuitable for the refutation of economic theory?

8. Conception and Understanding

What distinguishes the cognition of praxeology from that of history?

Why can't history be scientific?

Why can't we measure any constant relations between so-called magnitudes in the field of economics?

Why is action always speculation?

9. On Ideal Types

Historical facts are unique and unrepeatable. Yet what do they have in common?

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