Subject: Re: [lojban] (no subject)

From: [email-masked]
Date: Thu, 31 May 2001 13:58:34 EDT

In a message dated 5/30/2001 9:49:43 PM Central Daylight Time, 
[email-masked] writes:

> >{lo broda cu du loi broda} = {su'o lo broda cu du pisu'o loi broda}>
> >isn't quite right, since Leibniz's law won't work on the right to left 
> >move:
> >"loi broda carried the truck" does not entail "loi broda carried the truck"
> >and similarly for other predicates that are more than the individual
> >contributions.
> 
> Probably you meant one of those loi's to be lo.
> 
The second.

<But {lo broda cu du loi broda} does not mean that you can always
substitute the words {lo broda} for {loi broda} and get a
true sentence!

{lo ninmu cu du la meris} is true, but that certainly does
not mean that you can take {lo ninmu} in any true sentence
and replace it with {la meris} and expect to get a true sentence.>
But you should be able to replace any occurrence of {la meris} by {lo ninmu}, 
I think. Still, you are right that this is not about LL; that is just the 
traditional place to see problems with identity statements and I went there 
without examining the matter further. There is still something fishy about 
this theorem, but it is not clear to me exactly what it is -- beyond the 
intuition (which does not stand inspection) that an individual is no more a 
mass than it is a set (Quine's set theory excepted). The source seems to be 
that, while every broda is identical to some loi broda, not every loi broda 
is identical to some individual, but that is just the order of quantifier 
muddle again. sorry.

<I don't know. Is a mass of two broda, for example, not a member
of {lu'i loi broda}? Maybe it is not, I'm never quite sure how {lu'i}
et al are supposed to work. My first guess would be that
{lu'i ro loi broda} is the set of masses of broda, so it would be
a superset of {lu'i ro lo broda}, but I'm not really sure.>

My reading of the material on {lu'i} and {lu'o} and {lu'a} is that they 
simply move around among the various ways of treating the same individuals: 
as set, mass or distributively. That fits the examples on 134-5 and actually 
has some uses, unlike other possibilities, your suggestions included. I'm 
not sure, by the way, that {lu'i ro loi broda} is well-formed: {lu'i} doesn't 
take an internal quantifier (it is not itself a descriptor but a qualifier) 
and (loi broda} takes a fractional external. So lu'i ro lo broda = lu'i piro 
loi broda = lo'i broda and so on. (see my addition on descriptors).