The research reported in this book is mentalistic linguistics in the above sense, and the book's aim is to put forth and defend a means to determine, with some confidence, when to take a certain set of informant judgments as a reflection of properties of the Computational System, hypothesized to be at the center of the language faculty.

It may be important to note that while it is often stated that one of the goals of generative grammar is to characterize and predict "the possible (actual and potential) occurrence of all and only the grammatical sentences of a given language," such is not a concern of the present work as it is concerned with the language faculty (more precisely, the Computational System) rather than with language (more precisely a particular language or another) although we do draw from informant judgments on sentences of a particular language.

In the terms of Chomsky 1986, I am concerned with I-language, not E-language. As Chomsky states here and there, it seems to be a consequence of some unintended historical "accident" (i.e., the way Syntactic Structures was prepared and published, "in place of" Logical Structure of Linguistic Theory) that the false conception of the goal of generative grammar as noted above spread. The field of generative grammar seems to me to have been (badly) influenced by this over the years.