FOM: Polylogism

[Edwin Mares]

At 03:06 PM 3/3/99 -0500, Steve Simpson wrote:
>
>I disagree.  Marx was no truth-seeker.  Indeed, Marx made a major
>contribution to truth-denial, with his theory of *polylogism*, i.e.,
>the theory that there is no one absolute or universal logic.
>According to Marx, logic is conditioned by non-logical factors.  In
>Marx's specific version of the theory, the determining factor is
>social class.  According to Marx, there are competing logics such as
>`bourgeois logic', `proletarian logic', etc., based on social class,
>and the only arbiter among them is raw power or historical necessity.
>(This predated the Nazi theory of `Jewish logic', `Aryan logic', etc.)
>The economist Ludwig von Mises dubbed Marx's multiple-logic theory
>`polylogism'.  According to von Mises, Marx devised this theory in
>order to spare himself the necessity of refuting the arguments of the
>classical economists; he simply dismissed those arguments as being
>based on `bourgeois logic'.  But clearly it goes deeper than that.  In
>my opinion, Marx was actually hostile to all reason and objectivity.
>In this respect Marx was a forerunner of postmodernism, and obviously
>all the postmodernists pay a great deal of attention to him.
>
I don't want to defend the claim that there is a different logic for each
social class (or von Mises' interpretation of Marx), but rather a much
weaker and I think more sensible view. Some people seem to treat classical
predicate calculus as "the deep structure of rationality". On the other
hand, there are non-classical logicians, like myself, who think that
different logics are appropriate for different subject matters. On one
level, this is quite trivial: there are many specialist logics around
(dynamic logic, linear logic, temporal logics, etc.). But also certain
rules which are valid in classical logic seem out of place in certain
domains. Consider ex falso quodlebet: from A and ~A, infer B. This rule
seems out of place when making inferences about a piece of fiction, because
in that domain contradictions are allowed. We don't think that we can read
any old proposition into a story just because it contains a contradiction.
This sort of example shows that we are somewhat flexible in our logical
abilities. It would also seem that this flexibility should be taken into
account in a vertibrate theory of rationality.

Ed Mares


Edwin Mares
Department of Philosophy
Victoria University of Wellington
PO Box 600
Wellington, New Zealand

Ph: 64-4-471-5368