You may like or dislike this thesis, and I do care which.
An inquiry into sluicing and free choice
Lorenzo Pinton

Abstract:
This thesis deals with the different meanings generated by the following two
sentences:

  (1) a. You may have coffee or tea, but I don’t know which.
      b. You may have coffee or tea, but I don’t care which.

Whereas the former seems to presuppose that only one alternative is possible (and the speaker cannot tell which one it is), the latter appears to entail that both alternatives are possible to the addressee (and the speaker does not care which one the addressee will actually choose). In technical terms, while (1b) licenses Free Choice inferences, (1a) blocks them. We follow Aloni’s (2019) and Fusco’s (2019) intuition that the different readings are tied to the presence of the modal in the sluice (the partially elided wh-question) in (1a), and to the absence of the modal in the sluice of (1b). We ground this assumption through the notion of temporal orientation: leaving out the modal in the sluice in (1a) would result in an infelicitous sentence (such as ‘#You may have coffee or tea, but I don’t know which you have.’), creating a contrast with the future time of evaluation given to have by the modal may in the antecedent, and the present time of evaluation provided to the same event have by know in the consequent. Repeating the modal insures a match between the two event times. On the contrary, care in the consequent of (1b) is able to provide future time of evaluation even if the event in its scope is expressed with a present. It is so because while may and care both have future orientation, know has present orientation. From this we derive the different FC readings assuming a uniqueness presupposition triggered by singular which clauses. In (1a) this presupposition applies to the modal and generates a contrast with the FC reading of the antecedent according to which the possibility modal applies to multiple elements. Therefore, the Non-FC reading of the antecedent in (1a) is selected. On the other hand, in (1b) the uniqueness presupposition applies to the event itself and not to its possibility. Therefore, no contradiction is detected with the FC reading of the antecedent and FC inferences are thus permitted.
While this thesis is designed to provide an analysis of the puzzle in (1) for semantic denotations as such, without assuming any specific theory of FC derivation, we do improve the syntactic and semantic conditions that play a role in the licensing of sluicing.