Causal Counterfactuals and Impossible Worlds

Abstract

This paper is not directly in the service of either of the ambitious analytic projects of analysing causation in terms of the holding of certain counterfactuals, nor of analysing counterfactuals in terms of causal matters. It focuses instead on one of the traditional puzzles that connect the two that arise almost whatever one takes the connection between counterfactuals and causation to be. The puzzle has no neat label that I am aware of, but it arises in its clearest form when we consider counterfactuals involving antecedent states that involve a difference from the actual course of events at a particular time, and a consequent, at least in part involving a state somewhat later than the time of the antecedent difference. In the possible worlds framework, the puzzle is often put in terms of what other differences there in the relevant possible worlds where the antecedent is true. Do those worlds match ours with respect to nearly all their pasts until the time relevant to the antecedent? Do they require 'small miracles' relative to the laws of the actual world? Is their causal structure the same except for an 'intervention' on a state associated with the antecedent? . . . and so on. Let me label this problem the 'deviation problem' to suggest that it concerns what deviations from actuality would be required for the antecedent to be true, in the class of counterfactuals of interest.In this paper I will propose a novel solution to the deviation problem. This solution will have several signal advantages over a number of the better-known proposed solutions to this problem, though it also incurs some distinctive costs. I am not sure, then, whether something like it will turn out to be the best solution, though I am sure it deserves a run for its money alongside its better-

Law-Abiding Causal Decision Theory

“…But some are already convinced that we need impossible worlds to make sense of the relationship between action and the laws of nature. Nolan [2017] Nolan is saying that while counterfactual scenarios involve things going differently, those differences do not generally go all the way to the laws of nature. My dropping a cup might make a difference to whether the cup breaks, but not to whether Newtonian physics is true.…”

Counterpossibles

“…In the impossible worlds framework, this corresponds to the following principle (French et al., 2020) 11 : Some nonvacuists endorse this constraint (Jago, 2014; Kment, 2014; Krakauer, 2012; Mares, 1997). 12 Others reject it (Bernstein, 2016; Clarke‐Doane, 2017; Nolan, 1997, 2017; Vander Laan, 2004). Here's a potential counterexample:…”

“…Moreover, “this computer program” clearly refers to the actual lines of code the graduate student wrote. See Nolan (2017, p. 29) for another example.…”

Impossible Worlds

“…In particular, counterexamples have been proposed to (12.7), which follows from (SIC). Nolan (1997Nolan ( , 2017 offers these: (12.13) If intuitionistic logic came to be thought of as a much more satisfactory basis for mathematics by experts, and if intuitionistic investigations led to breakthroughs in many areas, … then intuitionistic logic would turn out to be correct after all. (Nolan 1997, 550) (12.14) If Gödel had believed Fermat's Last Theorem to be false, it would have been.…”