Message-Id: <m0qxKeb-00006eC@xiron.pc.helsinki.fi>
Date:         Tue, 18 Oct 1994 11:30:36 -0700
Reply-To:     "John E. Clifford" <pcliffje@CRL.COM>
Sender:       Lojban list <LOJBAN%CUVMB.bitnet@FINHUTC.hut.fi>
From:         "John E. Clifford" <pcliffje@CRL.COM>
To:           Veijo Vilva <veion@XIRON.PC.HELSINKI.FI>
Content-Length: 3221
Lines: 47

        Adding to my last posting, mehr Licht?
             Another feature of opaque contexts, which I forgot to men-
        tion, is that Leibnitz's Law does not work in them: from a=b and
        [a] we cannot infer [b].  This is certainly the case if one term
        of the identity is a description, since what fits (or is intended
        to fit) a description can vary with context.  It is less certain
        for proper names, since some logicians hold that names are rigid
        designators, referring to the same thing in all contexts (at
        least all those in which the thing named exists).  But proper
        names in natural languages do not seem to meet this requirement
        -- more than one thing can have the same name, for example, even
        in a single context.  Thus, ordinary proper names seem to behave
        pretty much like descriptions under this rule (as the Lojban
        placement -- and official reading -- of _la_ suggests) and had
        best be thought not to be replaceable under identity.
             I found in the avalanche of the last couple of weeks a note
        from lojbab that mentions that the mark for raised subjects is
        _tu'a _, which is then the opacity marker under the suggestion in
        that posting (_xe'e_ in its non-experimental form).
             OTOH some expressions in English contain event-referring
        expressions but seem to be transparent: " I saw someone shooting
        pool," for example.  This pretty clearly does imply that there is
        someone that I saw shooting pool.  Indeed, if it could be shown
        that there was no one shooting pool in my visual range, I would
        have withdraw my original claim, falling back to "I thought I
        saw..." or "It looked like ..." or whatever.  But notice that
        the basic claim is not exactly the classic English form of an
        event-referring expression, a "that"-clause or an infinitive. "I
        saw that someone was shooting pool" does seem to be opaque,
        approximately equivalent to "came to know ... by seeing" and so
        inheriting the opacity of "know," failing to export when I could
        not identify the player -- presumably by sight. Thus, we might
        argue that the object of "see" in the transparent case is not the
        event but rather just the subject, to which the event-reference
        is somehow attached.  That is, it may be that the analysis of "I
        saw someone playing pool" is not "I saw (someone playing pool)"
        but "I saw someone (playing pool)", which would both account for
        the transparency and fit in with our general notion that the
        object of seeing is an object not (generally) an event.  That
        leaves the question of how the "someone" and the "playing pool"
        are to be linked together, for it is not just that the someone
        was in fact playing pool but that I saw him doing it, so there is
        an event-referring expression here after all, though perhaps
        subordinately.  None of the obvious suggestions in Lojban (e.g.
        _poi_ or _noi_) seems quite right.  Comments and suggestions
        welcomed eagerly.
        pc>|83