Conversely, the fundamental error of regarding functional notions as categorial does not readily tolerate the extended c-command discussed in connection with (34). From C1, it follows that this selectionally introduced contextual feature delimits irrelevant intervening contexts in selectional rules. Notice, incidentally, that the speaker-hearer's linguistic intuition may remedy and, at the same time, eliminate nondistinctness in the sense of distinctive feature theory. Clearly, a descriptively adequate grammar is not to be considered in determining the traditional practice of grammarians. It may be, then, that most of the methodological work in modern linguistics appears to correlate rather closely with the system of base rules exclusive of the lexicon.
see also: WikiPedia -- Chomskybot