During my years at MIT (1983-1985 and Fall 1986 as faculty member, 1977 – 1981 as visiting scholar), I mainly worked on two research topics:
- the theory of silent syntactic positions (null pronominals and, more generally, null arguments, traces, etc.);
- the theory of locality.
There was a third and broader topic, dominant at that time, which was nourished by research on locality and null elements, and offered a framework for more specific technical work in comparative syntax:
- the proper treatment of language invariance and variation with parametric models.
What led many of us to study null elements at the time was the simple observation that knowledge of elements missing from the physical signal, the postulation of their presence in mental representations, and the way in which they were interpreted, were more likely to spring from inner necessities of the system of mental computations, rather than from association with, or induction from, specific pieces of external input. So, the study of silent positions seemed to offer a privileged access to what everybody was aiming at, an understanding of the system of mental computations. A core idea was that a theory of such elements should include:
- A characterization of where they can occur, what was called the “formal licensing” conditions.
- A characterization of how they can be interpreted on the basis of the overt context in which they occur, what was called the procedure of “identification”.
I personally worked a lot on licensing and identifications of null pronominals, with special reference to pro, and of traces, mainly arising from A’ dependencies. The study of null pronominals led to much work on the Null Subject Parameter; more generally, it contributed to developing the parametric approach to comparative syntax through the detailed study of a parametric option with richly articulated comparative consequences.
Another research direction on null elements, stemming from the attempt to work out the “identification” conditions for traces (in this case, the conditions permitting the connection between a trace and its antecedent) led to a long term project on locality and intervention effects, which gave rise, a few years later, to Relativized Minimality, and then to The Minimal Link Condition, locality on Agree, etc., all conditions which, in restrospect, can be seen as trying to express in slightly different technical ways the concept of minimal search.
Much progress has been made on specific aspects of these three topics, and they are all of actuality in current research. Suffice it to think of:
- Recent publications like Biberauer, Holmberg, Roberts, Sheehan, eds. (2009), with contributions bearing on the analysis of Null Subjects in Minimalist Theory.
- Much current work on the theory of locality, also in connection with the program of studying the cartography of syntactic structures.
- The current lively debate on the parametric approach and Minimalism, and, more generally, on how to best express a theory of syntactic variation (e.g., the Barcelona workshop last year, etc.)
I believe that these topics are so broad and central that they will remain on focus in syntactic research in the years to come. Some significant issues are the following:
- The theory of locality has been built along two distinct concepts, which are implemented in formal principles on separate tracks:
- Intervention: some kind of structurally defined intervener disrupts a local relation (RM, MLC, but also the Minimal Distance Principle, etc.)
- Impenetrability: certain configurations are impenetrable to rules (Island Constraints, Subjacency, CED, Phase Impenetrability,…) Is it necessary to postulate two distinct kinds of principles? Or can one envisage a unification? On what basis?
- Traces are generally assumed in minimalist syntax, but the necessity of assuming null pronominals (PRO and pro) is controversial (e.g.., under the movement theory of control and the “pronominal affix” approach to null subjects).
- Can one really do away with null pronominals?
- And what typology of null elements (including also A’ elements like null operators, null topics, etc.) can be assumed?
- Is syntactic variation expressible through the notion of parameter?
- If so, what is the format and locus of parameters? i.e., how and where are they expressed in a grammatical system?
- If not, what is the alternative?