Syntactic effects of lexical operations: Reflexives and Unaccusatives

As is well known, what appears to be the same verb, may often show up in very different syntactic realizations. In addressing such phenomena (or lexical structure in general), two distinct questions have been at times conflated: One is the question of the mapping (linking) from the lexicon (thematic structure) to syntactic structure, namely, which theta role should realize in which argument position. This is addressed by principles like the Theta criterion, Baker's (1988) UTAH, or Grimshaw's (1990) mapping of argument-structure to syntactic structure, as well as many other linking proposals. I will not be concerned here with this question. The other question is the structure of the lexicon itself, e.g. do the verbs in each group above, which appear to have different thematic structure, correspond to one or more lexical entries.