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A quick reply to Mike:
> > > > A related issue is whether parsing the syntax gives you the
> > > > logical structure. For example, although Lojban claims to
> > > > have an explicit and unambiguous grammar, this claim is
> > > > tantamount to being bogus, or at least fatuous, since all
> > > > the grammar does is generate the set of well-formed word
> > > > strings; the structure imposed by the grammar on the word
> > > > strings does not give you the logical structure of the
> > > > sentence. The rules for getting from the lexicosyntactic
> > > > structure to the logical structure have not been created
> > > > yet. (I exaggerate slightly: the grammar does yield predicate-
> > > > argument structure, but not much beyond that.)
> > >
> > > It is here that I am a little cloudy. Can you elaborate a bit
> > > more on the distinction between the logical structure of the
> > > language and the lexicosyntactic structure as you see it?
> > > Since you mentioned Lojban, would it be possible for you to
> > > give an illustration in that language, assuming time permits?
> >
> > Well, for example "ro nanmu cu prami lo ninmu" ("every man
> > loves a woman") parses with a structure reflecting the
> > predicate-argument structure, "[ro nanmu] [cu prami] [lo
> > ninmu]" (I am simplifying here, but not gratuitously
> > distorting the facts), according to the official grammar.
> > So nothing in the grammatical representation reflects the
> > quantifier scope, which in this instance is deemed to follow
> > from linear order.
>
> Okay, I see your point. A few issues crowd my mind at once:
>
> (1) While the formal syntax of the particular example you
> give indeed does not formally parallel the logical structure
> it is deemed to represent, nevertheless, the logical
> structure is clearly unambiguously established. Purely
> speculatively, could we not somehow re-analyze the syntax in
> order to reflect the logical structure? If so, would such
> a re-analysis satisfy your objection?
Yes. But such a reanalysis would not have been proved unambiguous.
> (2) Later on in your post, and also in one of kaliputra's posts,
> it was alluded that there are some areas in which a logical
> structure can *not* be unambiguously established from Lojban
> syntax. I have to confess that I am ignorant of these areas;
> I would have thought that by now all known glitches had
> been worked out. If there are still glitches, then my
> speculation regarding re-analysis in (1) is perhaps moot.
The glitches have very much not been worked out. Incredible
though it may seem, it was never a design goal of Lojban to
specify the logical structure of sentences, and rules of that
sort made their way piecemeal into Codex Woldemar (aka Refgram).
There are many unresolved issues, and their resolution is
de facto and de jure being left to usage.
Note too, again, that rules for deriving logical structure
from syntactic structure have not been rigorously formalized
or proved unambiguous.
> Rephrasing this thought as a question: in your view, does
> logical non-ambiguity always demand that the synactical
> structure parallel the logical structure? Or is it possible
> to have some sort of verifiably unambiguous mapping between
> the two types of structures, however clunky and inelegant
> this may turn out to be?
Based only on my experience of thinking about these matters,
I think you can enrich the logical structure with uninterpreted
bits of syntax, but it's hard to represent such things as
scope relations without having scope follow from syntactic
structure.
That one sentence doesn't do justice to your hugely interesting
question; we'll have to return to it in future discussion.
>
> (3) If indeed it turns out that in order to have a *verifiably*
> rigorous mapping between sentence sound and meaning, we are
> required to parallel the logical structure directly in the
> syntax, then I have grave concerns about the effect that such
> a requirement would have on the naturalness of the language.
Quite possibly. I myself don't feel that natlangs are as
'a-logical' as many conlangers make out, but it is certainly
true that natlangs aren't big on unambiguity, syntactic or
logical.
> In the example you give, the closest we come to capturing the
> logical structure using plain English as opposed to logicians'
> jargon is:
>
> - If something is a man, then it loves at least one woman.
>
> Or a bit briefer:
>
> - If it's a man, it's a woman-lover.
>
> It seems to me that any direct predicate structure
> representation will result in a clouding up of the proper
> scope. At the very least, a lot of care will be needed when
> using case tags or voice operations to make word order
> changes. And yet, surely every natlang (of which I know)
> will prefer the simple predicate construction over the
> conditional-subordination construction which seems required.
> I am not sure what the solution is. There seems to be
> drawbacks either way. This is a trivially simple logical
> expression, and yet already we have a dilemma.
As usual, I agree with all the points you make. One strategy
I use in Livagian is phonologically null logicosyntactic
structure. So you end up with something like "every man some
woman loves" at the level of phonology, but a fully explicit
structure logicosyntax.
Creating a minimally speakable loglang is a trivial task; it's
making it concise, naturalistic, etc. etc. that poses the
interesting challenge.
[...]
> In my list of goals, I placed at the top logicality, syntactic
> non-ambiguity, and semantic precision, each of which, to me,
> actually represents an aspect of the same overall objective.
> I listed naturalness immediately after these because of my
> sense that the requirements of logicality would inevitably
> somewhat strain naturalness, thus it was important to maximize
> it wherever possible. Thus, it is interesting to me to see
> how far we have to veer off from natlang norms in order
> to implement verifiably rigorous logicality.
It is interesting indeed. Engelangers probably differ about
whether they prefer to start with something naturalistic, and
then try to work various sorts of rigour into it, or whether
they start with the various sorts of rigour and then try to
make it user-friendly. Me, I am of the latter type. Katanda
and Lojban are both further towards the other pole (IMO).
--And.