Global constraints [Was: "Generative" serves them right]

[Emily Bender]

Re: The issue of global constraints and Raul's question about
where the constraints that make up the Binding Theory "live"
(i.e., how they fit into the ontology)...

I've always liked the idea of a grammar consisting of different
pieces (lexical items and constructions) that fit together however
they can.  All possible combinations license grammatical structures,
although only some of those structures (e.g., those that unify with
the initial symbol) count as sentences, and some others count as
non-sentential stand-alone types.  What I find appealing in this
is what it says about incremental processing:  When you've only
dealt with the first three words of a sentence, you can already
pick some possible structures as possible.

In contrast, any constraint that involves checking the whole thing
when you're done (e.g., Completeness and Coherence in LFG, the idea
that all features must have a value in Construction Grammar) means
that you can't know immediately if a partial structure will turn out
to be grammatical in the end.  The Binding Theory constraints seem
to be to have a similar flavor.

Is there a real difference here (between the rest of HPSG and the
Binding Theory or between HPSG and LFG/Construction Grammar), or
do these things all wash out if we get down to the underlying logic
of the formalisms?

Emily

SHALOM LAPPIN wrote
>
> One of the main distinctions between the MP and most other theories of
> formal grammar (HPSG, LFG, CG, TAG, and Arc Pair Grammar, for example),
> is that the MP incorporates conditions on sets of derivations
> (transderivational constraints) of either a global or a local character,
> while the other theories rely soley on local conditions on structures. A
> second major distinction is that most versions of the MP have only two
> interface levels, LF and PF, which are the output of a
> derivation. By contrast, the other theories generally define syntactic,
> semantic, and phonological well formedness in tandem at every level of
> structure. David Johnson and I explored these distinctions and others in
> detail in our book Local Constraints VS. Economy, CSLI, 1999. Together
> with Bob Levine we have been discussing these issues in the context of
> a debate with MP advocates in recent issues of NLLT. Our main concern is
> to show that the notion of grammar as a system exhibiting "perfect
> design", which lies at the cores of Chomsky's current program, has no
> obvious content. To the the extent that this is the case, the program
> is conceptually ungrounded. This seems to us to be a deeper and more
> basic flaw than the particular computational and empirical shortcomings
> of the framework (and we have tried to point out some of these in our
> book). We continue to find it remarkable that so many adherents of the
> MP have been apparently willing to accept the notion of perfect design
> without demanding clarification or discussion of this concept. y
>                                     Shalom
>