Re: heterodoxers are crackpots AND logic

[Paul Davidson <pdavidson@xxxxxxx>]

At 07:10 AM 8/27/02 -0700, you wrote:
> With regard to logical consistency, I'm quite sure
> heterodoxy or whatever would not want to be thought of
> as being "illogical."  However what does it mean to be
> "logical?"  This is not merely a semantic question:
> people who might be called heterodox or PK use all
> kinds of types of logic, such as deduction, induction,
> retroduction, etc.  Returning to the work of Sheila
> Dow, she rejects what she refers to as "classical"
> logic, which requires certainty, dualism, closed
> systems, etc.  She even claims that Keynes rejected
> such logic. Keynes' TP after all espoused a "logical"
> theory of probability, but one that was very different
> to its rivals.
>
> Using deductive logic can of course be useful.  If
> heterodoxers can show that orthodoxy is garbage by
> using the logic most favored by it - for example in
> Paul Davidson's work - that's powerful.  However,
> Dow's argument is that the nature of the world itself
> (or at least parts of it) might not lend itself to
> classical deductive logic, thus rendering that logic
> less powerful.


I'm sorry -- but the onus is on those who argue that deductive logic has no
role in discussing real world economics. I think I have already
demonstrated that can use deductive logic and deal with uncertainty
despite  your statement that

"the work of Sheila Dow, she rejects what she refers to as "classical"
logic, which requires certainty, dualism, closed systems, etc. " I

Is Keynes's (and my) work on liquidity and uncertainty and its implications
for employment, etc. irrelevant  or even worse -- for you state :

"She [Shiela Dow] even claims that Keynes rejected such logic." So is
Keynes's GT something Keynes would have rejected since it is based on
axioms and deductive logic.  If you don't think so just read the passage on
page 16 of the GT :

"Obviously, however, if the classical theory is only applicable to the case
of full employment, it is fallacious to apply it to the problems of
involuntary unemployment-if there is such a thing (and who will deny it).
The classical theorists resemble Euclidean geometers in a non-Euclidean
world who, discovering that in experience straight lines apparently
parallel often meet, rebuke the lines for not keeping straight-as the only
remedy for the unfortunate collisions which are occurring. YET, IN TRUTH,
THERE IS NO REMEDY EXCEPT TO THROW OVER THE AXIOM OF PARALLELS AND TO WORK
OUT  A NON-EUCLIDEAN GEOMETRY. SOMETHING SIMILAR IS REQUIRED TODAY IN
ECONOMICS."

"In that case, one would use logic that
> has some basis in the nature of the world.


I think it is clear from this passage and what follows that Keynes was not
only using deductive logic to attack the classical system for having
"postulates ...[that] are applicable to a special case and not the general
case" [ GT, p. 3] but also to present a deductive logical system that could
explain involuntary unemployment as the outcome of the actions of
self-interest individuals in a market, money-using entrepreneurial economy.

I do not think you have proved the case otherwise by citing Sheila Dow or
using the sound bite "different horses for different courses".  What
evidence do you have to indicate that Keynes's GT does not provide the
basis for developing logically the conditions in which involuntary
unemployment occurs.

Paul
Paul Davidson
Editor, Journal of Post Keynesian Economics
Economics Department - 523 SMC
University of Tennessee
Knoxville, Tennessee 37996-0550
phone # (865) 974-4221
fax # (865) 974-1686
home phone  (865) 692-0802
http://econ.bus.utk.edu/davidsonextra/Davidson.html