Analyses of the ellipsis identity condition must account for the fact that some syntactic mismatches between an 4 ellipsis site E and its antecedent A are possible while others are not. Previous accounts have suggested that the 5 relevant distinction is between different kinds of heads, such that some heads in the ellipsis site may mismatch while 6 others may not, and they have dealt with this sensitivity to a set of "special heads" with a built-for-purpose syntactic 7 identity condition which holds over and above semantic identity to constrain ellipsis. In this article I argue against 8 this approach and pursue an alternative which holds that identity is syntactic but "loose" in a precisely defined way.
9I show that the relevant generalization that accounts for syntactic identity effects in sluicing and VP-ellipsis-like 10 constructions concerns the position of variables in the antecedent, rather than the feature content of syntactic heads.
11I propose an implementation of syntactic identity which allows for the accommodation of additional antecedents, 12 with these being derived by a grammatical algorithm for generating alternatives, and I show that this implementation 13 derives the right kinds of looseness while restricting mismatches with respect to the position of variables, thus deriving 14 both the tolerable and intolerable mismatches between E and A without recourse to a specific condition regulating the 15 content of special heads. Much work on the ellipsis identity condition has revolved around the analysis of syntactic mismatches 20 between the ellipsis site E and its antecedent A. These fall into two broad categories: tolerable mismatches, 21 and intolerable mismatches. The existence of tolerable mismatches indicate that the identity condition 22 cannot be one of strict isomorphism between E and A, but rather something looser, and they have been used 23 by some (e.g. Merchant 2001, Merchant 2005, Potsdam 2007, Thoms 2013 to argue in favour of a strictly 24 semantic formulation of the identity condition, which allows the relevant differences in syntactic form.
26(1) a. I remember meeting him, but I don't remember when I met him.
27b. Decorating for the holidays is easy if you know how to decorate for the holidays.
28However, recent work (e.g. Chung 2013, Merchant 2013b, Saab to appear) has concentrated on demonstrat-
29ing the existence of intolerable mismatches: that is, mismatches between E and A which seem to cause the 30 identity condition to fail (attested by the ungrammaticality of certain construals of ellipses). The intolera-31 ble mismatches in question are of significance because they seem not to be ruled out by semantic identity 32 * For discussion and feedback I thank Matt Barros, Patrick Elliott, Anikó Liptḱ, Andrés Saab and the audience at the Leiden "identity in ellipsis" workshop, as well as four reviewers whose insightful comments improved this paper substantially. For help with data I thank Gillebrde MacMillan and all the staff and other members of the Gaelic-speaking community ...