It is well known that the identity condition on VP Ellipsis is not a condition on the phonological form or even the surface structure; rather it operates at some more abstract level. What this level is exactly has been debated in depth; I will adopt here the proposal in Merchant (1999) that the identity condition is a condition on LF.
I will first give a brief overview of Merchant's identity condition. Then I will show how it is compatible with NP Ellipsis. Finally, I will present a previously undescribed pattern, sensitivity to plurality/aspect, and show how it follows from the identity condition, given the right assumptions.
Fiengo & May (1994)2 were the first to propose that the identity condition on VP Ellipsis was a two part relation, consisting of a syntactic identity condition on antecedent and elided VPs, and a semantic identity condition between the first VP and the second.
Rooth (1992a) refines this analysis, drawing a connection between the processes of deaccenting and ellipsis. In his account, a phrase cannot be deaccented or elided unless the XP containing the antecedent entails something contained in the Focus-closure of the XP containing the elided phrase.
This hinges on Rooth's definition of Focus-closure. The Focus-closure or ``alternative semantics'' interpretation of a YP containing a focused XP is constructed as follows. First the ``ordinary semantics'' interpretation for that YP is constructed. Then the part of the interpretation corresponding to the focused XP is lambda extracted and allowed to range over all possible elements of the same semantic type3. For example, if the ordinary semantics and ``alternative semantics'' for [ American farmer] is as follows:
In other words the ``alternative semantics'' for [ American farmer] is a set of interpretations corresponding to Canadian farmer, Mexican farmer, and so on.4 The set returned by Focus-closure has an element for each intersective adjective, combined with farmer.
The operation of Focus-closure only returns this set of constituents for focused elements. The Focus-closure of a non-focused element (including deaccented and elided elements) is the same as the ``ordinary semantics'' interpretation.
Building on this, Rooth shows that the condition on deaccenting is simply that the XP containing the antecedent entail something that is contained in the focus-closure of the XP containing the deaccented phrase. (Rooth does his calculations at the level of sentences. Merchant adds -type shifting to allow Focus-closure to be used for other phrases as well.) This allows a ``specific'' IP to antecede a deaccented, more general IP (the italicized phrase is deaccented):
The IP she insulted can be deaccented, because its focus closure contains something entailed by the antecedent Mary called Frank a Republican:
Rooth then argues that this condition is exactly the semantic condition on ellipsis proposed by Fiengo & May.
Merchant further refines Rooth's identity condition on ellipsis. While the interpretation of the antecedent must be or entail an element of the Focus-closure of the elided phrase, just as in Rooth's account, Merchant also requires the elided phrase to be or entail an element of the Focus-closure of the antecedent. This second condition, making the relation between antecedent and elided phrase completely symmetric, replaces the syntactic surface condition of Rooth (and Fiengo & May).
This can be seen in the following example. The elided IP in the sentence below can only be interpreted as she called t a Republican, not as she insulted t. However, both of those phrases are valid deaccented phrases.
Merchant gives a general identity condition on ellipsis, intended to work for VP Ellipsis and Sluicing:
I retain the Focus-closure aspect of Merchant, because it captures the empirical similarity between deaccenting and ellipsis, but this is not crucial to my account. In fact, my account would be simpler if the identity condition could simply be logical equivalence ( ) between the antecedent and the ellipsis, modulo -type shifting.
I will now turn to some data that shows this identity condition suffices for NP Ellipsis.
Strict/sloppy ambiguity is available in NP ellipsis. This is predicted by Merchant's identity condition. The relevant examples to consider are ones like the following:
An account of (56) would go as follows. For the strict reading, the elided NP would have been picture of Mary.
For the sloppy reading, the elided NP is interpreted to have been picture of him/her where the pronoun is bound by the owner of the picture.
Note that this account assumes that at least some possessors (those of deverbal nouns, for example) are semantic arguments to their nouns.
A specific noun phrase can antecede a deaccented, more general noun phrase. But a specific noun phrase can only antecede an identical elided one, just as is predicted by Rooth.
A Focus-closure-based account will work as follows. The general NP, bicycle, can be deaccented. Schwinn entails bicycle, which is in the Focus-closure of bicycle.
However, ellipsis of the NP bicycle is not allowed. Bicycle does not entail anything in F-Clo(Schwinn), and thus cannot be elided7.
Deaccenting is allowed, since the antecedent entails an element of the Focus-closure of the deaccented phrase. However, ellipsis is disallowed, since the deaccented phrase does not entail an element of the Focus-closure of the antecedent.
VP Ellipsis is well known to be insensitive to the morphological form of the elided verb. Since the auxiliary preceding the ellipsis site determines the form of the verb in its complement, the morphological form of the ellipsis is recoverable.
Similarly, NP Ellipsis is insensitive to the morphological form of the elided noun. Since, in the usual case, there is no overt marker of the plurality of the DP outside of the NP, an elided NP will be ambiguous between singular and plural interpretations.
This makes perfect sense. NPs denote properties, not entities. Whether the DP refers to a singular entity or a plurality of entities should be calculated at the level of the DP, not the NP. The identity condition is satisfied for examples like (70)/(71) then:
However, if we know that Mary is a car collector, or that Bob entered many pictures in the contest, the plural interpretation is suddenly available. Even though one interpretation of the ellipsis site is more salient or preferred, both are available in the appropriate context, so the grammar should not rule out either interpretation.
There are, however, a range of exceptional circumstances in which the plurality/singularity ambiguity of the elided DP is eliminated.
Partitives, for example, mandatorily take a DP complement which is plural or denotes a group. So an elided NP in a DP complement to a partitive is only interpretable as a plural.
But an elided NP in a DP complement to a partitive which has a group noun as its antecedent remains ambiguous, since both the plural and the singular are possible complements to the partitive:
Subject-verb agreement also seems capable of eliminating this ambiguity. Although speakers vary on their judgments somewhat, no one judges these kinds of examples to be completely ungrammatical.
We should not attempt a syntactic or even a semantic analysis of these facts because context or knowledge about the world can interfere to limit the available interpretations as well.
Since most people have two eyes, and since two women don't ordinarily get married, there is a tendency to assume that these ellipsis sites are in plural DPs. But if we know, for example, that Bart was a battle-scarred pirate, or that Cindy and Tina were gay, then the singular interpretations suddenly become available interpretations.
So NP Ellipsis is insensitive to the morphological form of the noun, allowing ambiguity between plural and singular interpretations of the ellipsis site. There seems to be a preference for a singular ellipsis site in the absence of information to the contrary. And syntactic and contextual factors can interfere and push the interpretation in one direction or the other. But in general, this insensitivity to plurality parallels the insensitivity of VP Ellipsis to the morphological form of the verb in the ellipsis site.
The identity condition on VP Ellipsis is insensitive to negation:
We would expect the same thing in NP Ellipsis, and it does seem to happen:
This is not surprising at all, given the pattern in VP Ellipsis. A naive account would simply insure that NP Ellipsis targeted some node below the negative morpheme, which would sit in a functional projection above NP:
With two very semantically similar nouns, however, it is difficult to get NP Ellipsis to resolve to a split antecedent.
And even with a deverbal noun, it seems difficult to get a split antecedent:
It seems that NP Ellipsis may not allow split antecedency at all.
I have shown that a great deal of the same patterns present in the syntax and semantics of VP Ellipsis are present in the syntax and semantics of NP Ellipsis, and that the identity condition of Merchant accounts for the data.