Samuel Bostaph writes:

Mises refers to his own method of constructing theories of human action as
"praxeology."  It is different from both purely logical reasoning and math.

"Logic and mathematics deal with an ideal system of thought. The relations
and implications of their system are coexistent and interdependent.  We may
say as well that they are synchronous or that they are out of time.  A
perfect mind could grasp them all in one thought.  Man's inability to
accomplish this makes thinking itself an action, proceeding step by step
from the less satisfactory state of insufficient cognition to the more
satisfactory state of better insight.  But the temporal order in which
knowledge is acquired must not be confused with the logical simultaneity of
all parts of an aprioristic deductive system.  Within such a system the
notions of anteriority and consequence are metaphorical only.  They do not
refer to the system, but to our action in grasping it.  The system itself
implies neither the category of time nor that of causality There is
functional correspondence between elements, but there is neither cause nor
effect.
"What distinguishes epistemologically the praxeological system from the
logical system is precisely that it implies the categories both of time and
of causality.  The praxeological system too is aprioristic and deductive.
As a system it is out of time.  But change is one of its elements....So is
the irreversibility of events.  In the frame of the praxeological system any
reference to functional correspondence is no less metaphorical and
misleading than is the reference to anteriority and consequence in the frame
of the logical system."  (pp. 99-100, Human Action, 1966 ed.)

Mason responds:

Thank you, Samuel, for picking out that apt quote. After some hard slogging
I understand it, and resonate to it! On the bad side, it is prolix and
turgid, and padded with gratuitous Misesian neologisms. (The style calls to
mind The Mikado who would sentence certain offenders to "listen to sermons
by mystical Germans who preach from 9 to 4".) Yet it strikes a sympathetic
chord, now that I finally get it - or think I do.

Comte was more terse, if less complete, when he wrote that all science deals
either with relations of coexistence, or of sequence.

On the eve of Keynes, neo-classical economics, inspired by Clark's static
analysis, had pretty well limited the subject to relations of coexistence:
no praxaeology. The Austrians were notable exceptions, which helps explain
why Clark and Knight attacked them so strenuously. It also helps explain the
vacuum into which Keynes was able to rush and expand so fast, and why older
neo-classical avatars had so much trouble understanding him.

What still puzzles me is why the mass of economists rejected Austrian cycle
analysis and waltzed off with Keynes, instead. I surmise it had something to
do with clumsiness of exposition, coupled with Hayek's class-biased
application of the theory in which he focused entirely on lower wage rates
and a period of penance and suffering as the cure for depression. Wrong
reading of the Zeitgeist! He zigged when he shoulda zagged. 

Better explanations gladly received.

Mason Gaffney