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Re: Axiomatic ontology



Rob,

There is no contradiction there:

RF> I thought Russell's paradox might provide a hint where any
 > complete conception could tie itself in knots. A set that
 > both is and is not a member of itself. Maybe "the universe"
 > is that way.

There is no contradiction whatever in the assumption that a set
could be a member of itself.  The contradiction arises between
two other assumptions:

  1. The axiom that for every monadic predicate P(x), there
     exists a set of all the x's for which P is true.

  2. The construction of a special set:

        {x | ~memberOf(x,x) }

     In English, the set of all x's such that x is not a member of x.

There are two straightforward methods for getting rid of the
contradiction:

  1. The simplest is to drop axiom #1.  That means that there may be
     predicates such as P(x) for which there is no corresponding set.

  2. The other is to define a method of constructing sets that makes
     it impossible to form a set that contradicts axiom #1.

Both of these methods are used in various theories.

Finally, I have no idea what you mean by "that way".  One thing
that is certain is that anything that exists can be described by
a list (possibly a very long list) of simple statements that do
not contain any negations.  Since it is impossible to have a
contradiction without having at least one negation, everything
that exists must be describable by a list of consistent statements.

Therefore, nothing that exists can be self contradictory.

John