Phil Dowe’s research while affiliated with Australian National University and other places

David Lewis aimed to give an account of causation, and in particular, a semantics for the counterfactuals to which his account appeals, that is compatible with backwards causation and time travel. I will argue that he failed, but not for the reasons that have been offered to date, specifically by Collins, Hall and Paul and by Wasserman. This is significant not the least because Lewis’ theory of causation was the most influential theory over the last quarter of the 20th century; and moreover, Lewis’ spirited defence of time travel in the 1970s has shaped philosophers’ approach to time travel to this day.

Drawing on Earman’s (1986) definition of determinism and Lewis’ (Australasian Journal of Philosophy, 61, 343–377, 1983) best systems account of laws, in What Makes Time Special? (2017) Craig Callender develops an account of time as ‘the strongest thing’. The characterisation of this account apparently assumes no action at a temporal distance, an assumption that also underlies Earman’s account of determinism. In this paper I show that there is a way to define determinism that allows worlds with action at a temporal distance to count as deterministic, that action at a temporal distance is possible on a best systems account of laws, and hence that Callender need not make this assumption.