SUO: Re: KIF Syntax & Semantics & A Basic Ontology
Pat Hayes wrote:
>
> > > I have a little (ok, a lot) of trouble reading this due to
> > > the lack of care or maybe the different conventions in the
> > > use of quotation marks. I know it aint easy in ASCII, what
> > > with needing quotes for emphasis and all. But when you write
> > > something like this:
> > >
> > > > There is really only one complication that needs attention,
> > > > namely, that an expression of the form (P T1 ... Tn) can occur
> > > > both as atomic sentences and as a term in an atomic sentence.
> > >
> > > Do you mean:
> > >
> > > > There is really only one complication that needs attention,
> > > > namely, that an expression of the form "(P T1 ... Tn)" can occur
> > > > both as atomic sentences and as a term in an atomic sentence.
> >
> > Well, actually, no, though I admit that the way I put it is
> > not excruciatingly correct. The problem with your suggested
> > correction is that ordinary quotes turn the expression in question
> > into a name for that very expression, i.e., the expression left paren -
> > upper case P - space - upper case T - the numeral "1" - and so on.
> > And that is not what I mean, as "P", "T1", and "Tn" are *metavariables*
> > that can take any terms of the language as value; I don't mean to be
> > talking about that very expression. Hence, what are really needed here
> > are so-called Quine corners, or corner quotes, which work sort of like
> > the LISP backquote operator, in whose scope variables (properly marked)
> > can continue to function as variables that can take values. But we have
> > no corner quote ASCII characters, and rather than invent them, I simply
> > used the expression "of the form" as a sort of corner quoting operator
> > to tip off the reader that the expression to follow is a general schema,
> > and that "P" stands for any term and "T1 ... Tn" any row of terms.
> > (Though there may be other places where I end up using quotes as
> > corner-quotes where they might have been a danger of ambiguity --
> > I'm sure I could have been more careful still.)
> >
> > > As far as the substance of this suggestion goes, I know you are
> > > working in some other flavor, so maybe what I say will not apply,
> > > but I used to think that I could get away with this very thing --
> > > loving polymorphism as much as I do -- and I discovered to my
> > > considerable grief that I cannot, and so there is now a whole
> > > subsection of my dissertation that is devoted to saying why
> > > and to building a work-around. Basically, I had to create
> > > two different types of B domains, there distinguished by
> > > single and double underlines, one for the NP type (or
> > > noun phrase grammatical category) and one for the S type
> > > (or sentence grammatical category). Again, this may be
> > > a side-effect of my needing to preserve the option of
> > > a functional interpretation at all times, but you may
> > > want to think about it.
> >
> > I agree that quotation is a delicate matter indeed.
> > But I must say, Jon, that, in this case, I am quite
> > puzzled as to what you could possibly find problematic
> > here. I really don't see any reasonable interpretation
> > of the passage in question other than the one I intended.
> > I'm clearly not *using* the expression, and it's also clear
> > that I don't intend to be talking about just that one single
> > expression (with the ellipsis, it's not even a legal KIF expression).
> > That the expression is a schema for all KIF sentences of that form,
> > i.e., all atomic sentences) seems to me to be the only game in town!
>
> I might add that the row-variables (those whose first character is '@')
> provide just the expressive power one needs here in the language itself,
> since the use of a universally quantified row variable corresponds almost
> exactly to the informal but common usage of the three-dots convention to
> indicate some arbitrary sequence of marks, as in Chris' introductory
> discussion. The soon-to-be-proposed-new-KIF expression (P @x) has as
> its instances all expressions of the form indicated, ie any expression
> consisting of a sequence of lexical items and subexpressions comprising,
> from the left: an opening parenthesis, followed by the letter 'P' ,
> then by a finite number of KIF terms, then by a closing parenthesis.
>
> However, Jon's second extract seems to be referring not to
> the subtleties of quotation, but to the need, as he sees it,
> to maintain a sharp distinction between expressions which are
> thought of as referring to things (NP type) and expressions which
> are thought of as making assertions (S type). This is traditional
> in most versions of logic, but Menzelian ingenuity seems to have
> made this distinction unnecessary. One can always adopt it,
> if that feels more comfortable, of course, but there seems
> to be no pressing semantic need to do so, as far as we can
> determine. Jon, in case we have missed something, can you
> tell us what was the source of your grief?
>
> Pat Hayes
¤~~~~~~~~~¤~~~~~~~~~¤~~~~~~~~~¤~~~~~~~~~¤~~~~~~~~~¤
Pat,
My whole concern on the first bit pretty much boils down to
the hermeneutic or pragmatic issue of "reader's expectation".
When the present writer shifts his modus operandi to that of
being a reader, and he is reading along and sees an expression
of the form "an expression of the form ..." then he expects to
see something like a picket fence of marks that are suitably
inhibitory to his habitual mode of evaluative intepretation,
and having dug in his pause at the site of that well-marked
seraglio, to be able to peer over the edge of it and there
to gaze on some semblance, no more, no less, of the object
of his writer's intent and prospectively that of his own
heart's desire and wit's edification, whether unicorn or
virgin or both, allegorically speaking, as every reader
of this, granted charity, grace, or wit may soon abduce.
Now, aren't you glad that I tried to make my lay brief?
The other concern was yet another one of those lessons
that I learned the hard way, forced to the point of it,
amounting to an obstruction into which I ran full tilt
when, in spite of my natural traditionalism, I dared to
try and best my nature with a piece of ingenerity whose
phenotype gives it the appearance of being superficially,
in any case, very much akin to this Menzelian inheritance
that you nomenate here, still, it did not prove itself to
be inescapably mutagenic until I, somewhat late in the game,
got down to the brass syntactical business of trying to design
a rigorous proof-format for the correspnding expressions, and
then I discovered that this whole house of cards would fall
down around my ears unless I tossed in explicit rules for
converting back and forth between the two types -- and
you must believe me, I resisted this with all my might,
but then, perhaps my might is not so mighty, after all.
Anyway, this is how I remember it -- it's written up
in a part of my dissertation that I have not visited
in a year or so, and did not completely work out the
last details of my best fix -- I will go look for it.
Jon Awbrey
¤~~~~~~~~~¤~~~~~~~~~¤~~~~~~~~~¤~~~~~~~~~¤~~~~~~~~~¤