WHAT DO BOTH CAMPS AGREE ON, AND WHERE DOES THE DISAGREEMENT COME FROM?
It is evident, then, that both camps agree that knowledge of language has to be a matter of degree. To quote Chomsky:
A preliminary observation is that the term “innateness hypothesis”
is generally used by critics rather than advocates of the position to
which it refers. I have never used the term, because it can only mislead.
Every “theory of learning” that is even worth considering incorporates
an innateness hypothesis. Thus, Hume’s theory proposes specific innate
structures of mind and seeks to account for all human knowledge on the
basis of these structures, even postulating unconscious and innate knowledge.
The question is not whether learning presupposes innate structure – of course
it does; that has never been in doubt – but rather what these innate structures
are in particular domains.
Elsewhere Chomsky says that
Any non-vacuous theory of language, whether rationalist, empiricist,
behaviorist, or whatever, must put forth an innateness hypothesis. The
interesting questions have to do with the precise character of this hypothesis,
not its existence as a necessary component of any non-vacuous theory.
What transpires from an exchange of this kind is that there are theorists who consider themselves either empiricists (like Sampson) or rationalists (like Chomsky and Pinker), and that it not a matter of contention whether there are any innate mechanisms, but rather what these innate mechanisms constitute.
It seems to be quite impossible to define rationalism and empiricism in a testable way, and that categorically distinguishes them. Due to these problems, the historical difference between the nativist and the empiricist will be ignored. When these terms are used here, “nativist” will be used to refer to Chomsky’s (and Pinker’s) view, whereas “empiricist” will be used to refer to Sampson’s.