What is praxeology?

Glossary definition: The general theory of human action: the a priori science that deduces its conclusions from the axiom that man acts. Economics is its most fully developed branch. Its theorems do not depend on the particular content of an action, or on its place and time; they hold for every action as such.

Definition

Praxeology is the general theory of human action. It starts from an axiom that nobody can deny without confirming it: that man acts, that is, uses means to attain ends he himself chooses. From this it deduces, by logical reasoning, laws that hold for every action, in every place and time. Economics is its most fully developed branch.

The word

The word is formed from the Greek prâxis (action) and lógos (reason, account). As French praxéologie it was used by Louis Bourdeau in 1882 and later by the philosopher Alfred Espinas; Ludwig von Mises made it the name of his science in Human Action (1949). This site, «Πραξεολογία», takes its name from it.

What follows from the axiom

Since man acts, he chooses between alternatives, so every choice has an opportunity cost. Since action takes time, man prefers to attain his end sooner rather than later: time preference. Since he values units of a supply, the value of the last unit falls as the supply grows: diminishing marginal utility. Since every exchange happens because both sides expect to gain, value is subjective.

Praxeology and history

The laws of praxeology are not “verified” by experiments, as in physics, because the conditions of human life cannot be isolated; they are true a priori, like the propositions of logic and mathematics. History does not test them; rather, praxeology helps us understand history. That is why the Austrian School rejects positivism in economics, the idea that economic laws are found in statistics.

In the original“Praxeology rests on the fundamental axiom that individual human beings act, that is, on the primordial fact that individuals engage in conscious actions toward chosen goals.”

Murray N. Rothbard, “Praxeology: The Methodology of Austrian Economics” (1976) · mises.org ↗

In the original“Praxeology is a theoretical and systematic, not a historical, science.”

Ludwig von Mises, Human Action, ch. II, §1 “Praxeology and History” · mises.org ↗

Sources: Ludwig von Mises, Human Action (1949), Introduction and ch. I–II · Murray N. Rothbard, “Praxeology: The Methodology of Austrian Economics” (1976) · Wikipedia — Praxeology