Praxeology

Praxeology (Gr. πρᾶξις (praxis) "action", λόγος (logos) ″talk, speech″) is the deductive study of human action, based on the notion that humans engage in purposeful behavior, as opposed to reflexive behavior like sneezing and inanimate behavior. According to its theorists, with the action axiom as the starting point, it is possible to draw conclusions about human behavior that are both objective and universal. For example, the notion that humans engage in acts of choice implies that they have preferences, and this must be true for anyone who exhibits intentional behavior.

The most common use of the term is in connection with the Austrian School of Economics, as established by economist Ludwig von Mises.

Coinage of the word praxeology is often credited to Louis Bourdeau, the French author of a classification of the sciences, which he published in his Théorie des sciences: Plan de Science intégrale in 1882:

On account of their dual natures of specialty and generality, these functions should be the subject of a separate science. Some of its parts have been studied for a long time, because this kind of research, in which man could be the main subject, has always presented the greatest interest. Physiology, hygiene, medicine, psychology, animal history, human history, political economy, morality, etc. represent fragments of a science that we would like to establish, but as fragments scattered and uncoordinated have remained until now only parts of particular sciences. They should be joined together and made whole in order to highlight the order of the whole and its unity. Now you have a science, so far unnamed, which we propose to call Praxeology (from πραξις, action), or by referring to the influence of the environment, Mesology (from μεσος, environment).

However, the term was used at least once previously (with a slight spelling difference), in 1608, by Clemens Timpler in his Philosophiae practicae systema methodicum:

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