This dissertation studies counterfactual conditionals in English. Counterfactual conditionals typically come with inferences that their antecedent and their consequent are not true in the actual world (written CF-p and CF-q, respectively).
(1) If John had taken the bus, he would have been on time.
CF-p: John did not take the bus
CF-q: John was not on time
Focusing on CF-q, the dissertation answers the question of what contextual conditions must be met for CF-q to arise, by looking at cases in which the inference gets cancelled. I show that CF-q can be cancelled in a number of different contexts:
- in some but not all conditionals that have the words 'also' or 'still' in their consequent;
- in a set of conditionals when uttered with a specific intonation contour.
Empirically, I show that when 'also' focus-associates with material in the antecedent, it cancels CF-q, but when it associates with material in the consequent it does not. This difference in focus association is reflected in the prosodic properties of the particle 'also' in the conditional.
The first step of the analysis is to find a property that unites the different CF-q-cancellation contexts. I argue that what they have in common is their making salient more than one cause for the same consequent (a multiple cause context). In the case of 'also', association with focus determines where focus alternatives are generated, which in turn determines whether a single or multiple causes are made salient.
The second step of the analysis is to show that conditional perfection (strengthening conditionals to biconditionals) is a necessary ingredient for the CF-q inference to arise, an idea sketched by Karttunen (1971). The crucial prediction is that in contexts in which no conditional perfection occurs, CF-q is not generated either.
Finally, I show that multiple cause contexts do not trigger conditional perfection, which in view of the above-mentioned prediction completes the analysis. Moreover, because conditional perfection has been analyzed in terms of discourse structure and exhaustive answers, we obtain a new set of theoretical tools to study counterfactuality as a discourse phenomenon.