Message-Id: <m0rhm5k-00001pC@xiron.pc.helsinki.fi>
Date:         Thu, 23 Feb 1995 17:33:55 EST
Reply-To:     jorge@PHYAST.PITT.EDU
Sender:       Lojban list <LOJBAN%CUVMB.bitnet@FINHUTC.hut.fi>
From:         jorge@PHYAST.PITT.EDU
Subject:      Re: On {lo} and existence
To:           Veijo Vilva <veion@XIRON.PC.HELSINKI.FI>
Content-Length: 2506
Lines: 69

And:
> I assume that by default every bridi is {dahinai}, unless there
> is overt {dahi}. So {lo ninmu cu nanmu} = {dahinai lo ninmu cu
> nanmu}, which says:
>
>    [In some universe, Ex x is a woman] and [in this universe,
>     x is a man]
>
> Perhaps if we allow this universe to contain individuals who
> also exist in other universes, that could be true. It depends
> on your metaphysics, so Lojban should be neutral on this
> matter.

I don't understand. Suppose I dream that I'm a woman. Then
it is true that {lo ninmu cu nanmu} right? All we need is
that some man sometime dreamt that he was a woman for the
claim {lo ninmu cu nanmu} to be true.

> > So you are accepting that {ro broda cu broda} can be false.
> > To me, that is an abomination.
>
> I am accepting it can be false. I don't see why it's an
> abomination. I don't even find it counterintuitive.

Not only can be false, but must be false. Here is the proof:

For the broda under consideration, find a ko'a such that
{ko'a broda} is false. (If there is no such ko'a, then broda
must be very peculiar, but for most broda there will be one).

Now imagine a universe where {ko'a broda} is true.

Then {ro broda cu broda} must be false, because there is at
least one {lo broda}, namely ko'a, which na broda.

> > then there can be no argument that {da poi broda} is equivalent to
> > {lo broda}, just as {roda poi broda} is equivalent to {ro broda}.
>
> I think neither of these equivalences hold. (I have decided to
> assume option [3] on my list of possible meanings for {lo}, on
> the grounds that it is most consistent with current usage.)

Consistent? It makes practically every claim about {lo broda} true:

Say I want to prove that {lo broda cu brode} is true.

All I need to do is find something that really is a brode in this
universe. Then imagine a universe where that something really is a
broda, and voila {lo broda cu brode} becomes true in our universe.

In other words, if for some da, {da brode} is true, then for every
broda, {lo broda cu brode} is true.

What is the point of having {lo} if every claim made with it
is vacuously true?

> Can the following both be true at the same time?
>
>   {mi skicu lo nalci be mi}
>   {no da nalci mi}
>
> I want these both to be true at the same time.

They can't both be true, they are contradictory (assuming all tenses
are the same, no tricks like {mi skicu lo pu nalci be mi} and
{no da ca nalci mi}, or worse: {mi skicu lo ka'e nalci be mi} and
{no da ca'a nalci mi}).

Jorge