Message-Id: <199604051848.NAA09246@locke.ccil.org>
Date:         Fri, 5 Apr 1996 18:21:33 +0100
Reply-To: ucleaar <ucleaar@UCL.AC.UK>
Sender: Lojban list <LOJBAN@CUVMB.BITNET>
From: ucleaar <ucleaar@UCL.AC.UK>
Subject:      Re: intensional sets of bridi
To:         lojban@cuvmb.cc.columbia.edu
Content-Length: 1186

This took a month to cross the Atlantic. Hence the late reply.

Jorge:
> And:
> >How would one say in lojban "the set of propositions of the form
> >x is broda"?
> I think I would say: {lo'i du'u ke'a/ce'u broda}

That's ingenious, but you lose the parallelism between "x is broda"
and "for some x it is the case that x is broda". Unless, that is,
we can bind ceu, as in {suo ceu zou ceu broda} or suchlike -
with {ceu} equivalent to the logician's "x".

> >{lo,i duu da broda} won't do, because that means
> >the set of propositions of the form Ex x is broda.
> A singleton, right?

I believe so.

> >What one needs
> >is a way to cancel the default interpretation of {da} as {suo da}.
> I prefer not to tamper with that. {da} is the bound variable, why
> use it for the function of unbound variables?

Fair enough, so long as we have a way to do unbound variables, which
preferably is formally related to the way to do bound variables.

> >How? Could we have cmavo (in UI) to toggle between default
> >interpretations?
> I thought you were against the use of UI for such things.

But it would be metalinguistic, toggling between "{da} means [Ex x...]}
and "{da} means [x...]".
===And