NetNews Usenet Archive 1992 #23/NN_1992_23.iso/spool/sci/logic/1674

Internet Message Format | 1992-10-07 | 3.3 KB

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From: [e-mail] (Gary Merrill)
Newsgroups: sci.logic
Subject: Re: The Mathematical Universe
Keywords: inconsistent multiplicities
Message-ID: <[e-mail]>
Date: 7 Oct 92 14:06:36 GMT
References: <[e-mail]> <[e-mail]> <[e-mail]> <[e-mail]>
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In article <[e-mail]>, [e-mail] (Stephen Bloch) writes:
|> [e-mail] (Randall Holmes) writes:
|> >|> No, my view is that there is only one universe, and this includes all
|> >|> of the "possible worlds", _all_ of which are actual.  I am a possible
|>
|> and [e-mail] (Gary Merrill) replies:
|> >But certainly there *is* a distinguished world (which we normally refer
|> >to as the "actual" one).  You may say that *all* of the possible worlds
|> >are actual (or real, or whatever), but if you wish to retain a distinction
|> >between what *is* and what *might be*, then *some* distinction must be
|> >made.  No?  If not, I don't see how to distinguish between fact and fiction.
|>
|> Imagine I live in a suburban neighborhood containing lots of nearly
|> indistinguishable houses (in fact, to avoid being able to say "the house
|> at the northwest corner," let's suppose this suburb extends infinitely
|> in at least one dimension.  God, how depressing!)  I can still refer to
|> "the house," and everyone who hears me will understand that I mean
|> "the one I'm in."  If somebody else, living in a different house, says
|> "the house", she means the one's SHE's in.  The statement "A cat lives
|> in the house" may be fact in one and fiction in another.
|>
|> This entire "neighborhood" of possible physical worlds is a subset of
|> The Logical Universe (comprising "things that could be").

Yes, but what you have provided here is just a general account of how
indexicals are handled in our language (and in formal languages).
It is still the case that among the indices there often is a *special*
one:  I, now, here, the actual world, ...

If all you are interested in is theorems concerning statements with
indexicals in them, there *may* indeed be no reason to single out
a special one.  Even if there is, the content of these theorems may
be of *logical* interest only in that they have no empirical content.
For example, I recall a system of David Kaplan's in which
"I am here now" is a theorem.  But there is *still* an important
distinction not captured by the set of theorems.  *I* am
typing *this*, and *you* are not -- though you *might* be.

As a logician, I can say "There is nothing special about the actual
world.  It's just one of the possible ones."  But as a *scientist*
or as an epistemologist, there certainly *is* something special.
And this usually is captured by saying that the actual world is
*real* and the other possible worlds are not.
--
Gary H. Merrill  [Principal Systems Developer, C Compiler Development]
SAS Institute Inc. / SAS Campus Dr. / Cary, NC  27513 / [phone]
[e-mail] ... !mcnc!sas!sasghm