John Sowa wrote:
> ...  (01) 
> When we want to talk about ontology independently of any particular
> implementation, I suggest that we use the following terminology:  (02) 
> 1. A class is a set whose membership is specified by a monadic
> predicate that designates a property shared by every member
> of the set.  (03) 
I would resist defining a class as a "set" (a word which has hundreds
of meanings, but i take to mean a mathematical set). A mathematical
set is constant and defined by its members -- which never change. Two
distinct sets can not have exactly the same members. A class (in
computational ontology), on the other hand, having its membership
defined by a property, can have its membership change over time (in
a 3D+1 world model). Even a 4D model, should allow for hypotheticals,
in which case the membership of the class can be different for the
different hypotheses.  (04)
Other than this, i agree with John Sowa.  (05)
-- doug foxvog  (06)
> 2. Each word in a natural language has one or more word senses.
> Each word sense can be informally defined by a phrase in a
> natural language or formally defined by a predicate in some
> version of logic.
>
> 3. A lexicon is a collection of words whose word senses are
> defined informally in a natural language or formally
> by predicates in some version of logic.
>
> John
>
>  (07) 
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