From LOJBAN%CUVMB.BITNET@uga.cc.uga.edu Tue Nov 15 00:38:28 1994
Message-Id: <199411150538.AA03424@nfs1.digex.net>
Date: Tue Nov 15 00:38:28 1994
From: bob@GNU.AI.MIT.EDU
Subject:      Re: Ralph believes someone is a spy
In-Reply-To:  <9411150214.AA11653@albert.gnu.ai.mit.edu> (message from Logical
              Language Group on Mon, 14 Nov 1994 16:23:00 -0500)
Status: RO

    > > To not believe in something, one must acknowledge its
    > > existence.  ex.  To consciously not be prejudiced requires
    > > knowledge of prejudice.  To not believe in God requires
    > > acknowledgment of God's existence...

In addition to the nice distinctions that John Cowan made, it is worth
noting that this exhibits a confusion of map with territory, a
confusion between {lu'e} and {la'e}.

Also, it is a good idea to substitute `purple flying elephants' for
`God' so as to avoid confusion with the centuries' old theological
argument with which this issue is associated.

Suppose I want to make a judgement whether purple flying elephants
exist `for real'.  Do I have to first acknowledge they exist?  What
does `acknowledge' mean in this case?  Or can I hypothesize what I
might observe if purple flying elephants existed (and then search for
evidence)?

On the other hand, suppose I want to make a judgement whether purple
flying elephants exist in someone's imagination...  Do I have to first
acknowledge they exist in someone's imagination?  ...  Is that
relevant?

The question is essentially an issue of mapping: does the map I have
apply to the world `for real' (according to whatever epistemology I am
using)?.

Simply put, maps do not necessarily imply worlds;
otherwise treasure maps would more often lead to gold.


    > 3)    (Ex) (x is PFE) . (Ralph believes (~ (x exists)))
    >       PFEs exist, and Ralph believes they do not exist.

In this case, if Ralph were speaking Lojban, he would use {le} rather
than {lo}.  I, on the other hand, knowing that PFEs exist, would use
{lo}.  Ralph and I might then have a discussion, or he might ignore my
attempt to claim a reality different from his.

    > 4)    (Ex) (x is PFE) . ~ (Ralph believes (x exists))
    >       PFEs exist, and it isn't true that Ralph believes they exist.

Same here. Ralph would use {le} when talking about PFEs.

    > 5)    Ralph believes (~ (Ex) (x is PFE))
    >       Ralph believes that nothing exists which is a PFE.
    >       = Ralph believes there are no PFEs.

In this case, Ralph might use {lo} if he figures he is talking in a
context in which PFEs are presumed to exist, even though in `real
life' they do not.

    > 6)    ~ (Ralph believes ((Ex) (x is PFE))
    >       It is not true that Ralph believes that PFEs exist.

Yet again, Ralph might or might not use {lo} (or {loi})
depending on context.


    .i xu Ralf a mi pu pu'i viska loi zirpu je vofli xanto

    Is it true or false that Ralph and/or I can and have seen a
    purple and flying elephant?