Abstract:

We suggest a semantics for counterfactuals according to which the truth conditions for counterfactuals refer to probability measures. The semantics is made precise and studied in different versions which are related to each other by means of representation theorems. Despite its probabilistic nature, we are going to show that the semantics, and the resulting system of logic, may be regarded as a naturalized version of David Lewis' semantics and logic of counterfactuals. The results of our investigation are used to assess a claim put forward by Hawthorne and Hajek, i.e., the thesis that most ordinary counterfactuals are actually false.