David and ProDrop

[stassen]

David Gil wrote, on the subject of Pro-Drop:

> I find it rather suprising that we are still trying to force languages
into black-and-white categories like "pro-drop" given the overwhelming
evidence to the effect that so much is actually gray:  separate words
blend into clitics which then shade into affixes; the distribution of
would-be pronouns varies as a function of their number, gender and
person, and the tense and aspect of the verb; and above all the
acceptability of "dropping" varies in accordance with a myriad of
discrete and continuous contextual factors.>

David is right, of course. So why don't I like his answer? Perhaps it's
because it is a bit too easy for my taste. I have this dark feeling that
his comments on ProDrop could well be made about any typological parameter
ever proposed, and that his 'relativism' - right though it is, of course -
might end up destroying the gentle art of doing typology before it has even
started. The fact is: languages clearly differ in the possibility of
leaving their subject position unfilled. Some strands in post-war
theoretical linguistics have made a big deal out of this, claiming that it
is an explanatory factor for quite a lot of things. There are two questions
here. First: is the concept of ProDrop clear enough? And then: are the
claims about its alleged 'basicness', and about its typological
consequences, correct?
   Anybody who has done any serious typology will have found to his/her
discontentment that things are never straightforward. To give you just one
example from my own experience: does the language in question have a zero
copula or not? Well, some do, some clearly don't, and in between there are
all sorts of weird cases, having to do with person, tense/aspect, and "a
myriad of
discrete and continuous contextual factors". Still, I hold that the
presence or absence of a zero copula is a significant typological
parameter, which may not be caused by anything, but which certainly has its
influence on other parameter settings. All kinds of diachronic change are
of course going on all the time, and they are interesting in themselves:
why is it that zero copulas are on the wane, and Irish is becoming
Non-ProDrop? I am of the opinion that it does not help our science to
trivialize such questions and to shift them off to the pragmatic/stylistic
waste-basket.

Leon.