autonomy, Plato's Problem, and deep structure

[Brian MacWhinney]

I would like to second Martin Haspelmath's take on the importance of Plato's
Problem in the definition of the Chomskyan program.  Since 1965, Chomsky has
emphasized the role of the Logical Problem of Language Acquisition (LPLA) in
generative theory.  The formulation of the LPLA was an intellectual move
necessitated by the commitment in 1957 in Syntactic Structures to deep
structure.  The "discovery" of deep structure was, in turn, the achievement
that justified the introduction of transformations and the application of
automata theory to language.  As a result of these linkages, the commitment
to deep structure became central to the Chomskyan program.

In Plato's cave, true ideas are only seen as reflections.  However, we often
don't really need to look at the linguistic input at all, according to
Chomsky, since the true shape of the deep structure of language is resident
in our minds from birth.

It is possible to imagine routes to deep structure that do not go through
Plato's cave.  Competence-performance and introspection regarding degrees of
grammaticality provide one such route.

I agree with Martin, Edith, and others that the autonomy of syntax is not a
crucial support for deep structure.  For example, Freud's deep structure is
nicely grounded on claims about biological drives and developmental
principles.  Freud's example shows that there is no reason in principle that
a functionalist theory in linguistics could not be grounded on a deep
structure that was surrounded by a shell of protective concepts such as
competence-performance, LPLA, sentences instead of utterances, the ideal
speaker-hearer, degrees of grammaticality, and the rest.  However, I doubt
that many of us would be attracted to a functionalist theory of this type.
For this reason, I think that a willingness to minimize the role of an
abstract, underlying deep structure that has no easy match to observed facts
about learning, processing, and physiology is the fatal flaw in the Chomskyan
program.

Having said this, I wonder whether Martin and Edith really want to say that
the functionalist needn't care much about language acquisition.  I agree that
people in language development have not done a good job of showing
functionalists why learning is important.  But, if functionalism wants to
achieve explanation, it cannot ignore learning.

--Brian MacWhinney