functionalism and explanatory depth

[Martin Haspelmath]

Dick Hudson asks:

> So maybe *any* explanation is by definition functional, even if the
word
> 'function' isn't used?

Chomskyans wouldn't like to hear it, but in a sense, this is true. I
would put it as follows:

Functionalists are primarily interested in explaining language
structure, whereas Chomskyans are interested in this only secondarily.
Their primary interest is explaining Plato's Problem, the possibility of
language acquisition despite the poverty of the stimulus. This involves
the postulation of UG as the central explanatory hypothesis, and the
fleshing out of UG as the central descriptive task.

We have no disagreements when describing low-level generalizations,
which are of course also explanations in a sense (e.g. the rule that
English nouns form their plural by adding -s, which explains that the
plural of _book_ is _book-s_). But when it comes to higher-level
generalizations, we differ, because Chomskyans never seek
generalizations going beyond the language system. So some obvious
functional explanations have no status in Chomskyan linguistics (e.g.
the economic-motivation explanation for universal overt marking in
plurals). Thus, in a way, Chomskyan linguists are more modest as far as
the level of explanatory depth is concerned.

They generally don't admit this, but I've found a remarkable quotation
concerning diachronic linguistics:

"...people seeking a substantive theory of change [i.e. functionalists,
MH] are too ambitious, too principled, and seek to explain too much..."
(David Lightfoot, The development of language, Oxford: Blackwell, 1999,
225)

 Martin

--
Dr. Martin Haspelmath (haspelmath at eva.mpg.de)
Max-Planck-Institut fuer evolutionaere Anthropologie, Inselstr. 22
D-04103 Leipzig (Tel. (MPI) +49-341-9952 307, (priv.) +49-341-980 1616)