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Jordan: > On Sat, Nov 09, 2002 at 07:21:40PM -0500, John Cowan wrote: > > Jordan DeLong scripsit: > > > But there are no unicorns... It's equally true that they're all > > > green with purple dots, whatever you may believe > > > > The pc/John/And/maybe-xod viewpoint is that it's equally false to believe > > these things -- or, if you prefer, meaningless to say them > > I definitely prefer meaningless -- a false proposition implies every > proposition, no matter whether it is true or not -- so they are > certainly true statements > > > > However, regardless of whether universals import, you can universally > > > claim anything about things which don't exist in any universe, > > > provided that the universe is nonempty if you use a importing > > > universal quantifier, and it is true: > > > Ax((Fx & ~Fx) -> Gx) > > > is true for any universe, and any predicates F and G. (A false > > > proposition implies all propositions -- we know Unicorn(x) is going > > > to be false in this universe, just like we know Fx & ~Fx is always > > > false, so we can infer anything from it, such as white(x), purple(x)...) > > > > Absolutely. And you say that in Lojban using "ro da ganai ..." > > Right; but if ro <foo> doesn't also mean the same thing, our system > is inconsistent Whose system is inconsistent? "ro da in-this-world ga na unicorn gi broda" is not meaningless, though it is not very interestingly true. But "ro in-this-world-unicorn cu broda" is meaningless (I am agnostic about whether or not it is true, but it is certainly not something anybody would want to say). This is because the former selects 100% of everything, while the latter selects 100% of nothing. --And.