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Re: [jboske] Opacity and belief



And Rosta scripsit:

> For Clark Kent and Superman, I think it is clear that
> they are not synonymous. 

[snip]

> Similarly, I think that "water" and "H2O" are not intensionally
> equivalent but "wolfram" and "tungsten" are. 

I think you are confusing *a priori*-city with necessity. It's true
that we discover that Clark Kent is Superman, or that H2O is water,
only by *a posteriori* investigation, but that doesn't mean that there
are possible worlds in which Superman is not Clark Kent. There might be
someone very *like* Superman who was not Clark, but that person would
not *be* Superman. (Of course Superman might have been adopted by a
different family and therefore bear a different mundane name, but that
wouldn't affect his identity.) In short, identity holds necessarily if
it holds at all.

This is IMHO easier to see in the case of water. If water were not
H2O, it simply would not have the properties that we ascribe to water: a
highly polar substance, with a very large specific heat, liquid through a
specific range of temperature. Hilary Putnam's Twin Earth, where water is
not H2O but something with a very different ("highly complex") chemical
formula, just isn't physically possible. 

As for the wolfram/tungsten case, this too was discovered *a posteriori*:
a German and a Swedish miner compared notes, or groups thereof, and
found they were talking about the same stuff.
already be handlable in Lojban. Any > noninterchangeability of "wolfram"
and "tungsten" would have to be > done by using an "assent to" predicate
with a sedu'u sumti. > > --And. > > To unsubscribe from this group,
send an email to: > jboske-unsubscribe@yahoogroups.com > > > > Your use
of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/ > >


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"May the hair on your toes never fall out!" John Cowan
--Thorin Oakenshield (to Bilbo) jcowan@reutershealth.com