Stephen Barker

The standard view about counterfactuals is that a counterfactual (A > C) is true if and only if the A-worlds most similar to the actual world @ are C-worlds. I argue that the worlds conception of counterfactuals is wrong. I assume that counterfactuals have non-trivial truth-values under physical determinism. I show that the possible-worlds approach cannot explain many embeddings of the form (P > (Q > R)), which intuitively are perfectly assertable, and which must be true if the contingent falsity of (Q > R) is to be explained. If (P > (Q > R)) has a backtracking reading then the contingent facts that (Q > R) needs to be true in the closest P-worlds are absent. If (P > (Q > R)) has a forwardtracking reading, then the laws required by (Q > R) to be true in the closest P-worlds will be absent, because they are violated in those worlds. Solutions like lossy laws or denial of embedding won't work. The only approach to counterfactuals that explains the embedding is a pragmatic metalinguistic approach in which the whole idea that counterfactuals are about a modal reality, be it abstract or concrete, is given up.

Must counterfactual analyses of causation appeal to chances and chance-raising in order to tame indeterministic causation? It is generally thought so. 1 Against the grain, I contend that appeal to chance-raising is not required to analyse chancy causation. In Section 1 below I argue that the standard cases motivating the chance-raising analysis – cases such as bombardments of radioactive atoms causing the decay of those atoms – should be treated as instances of preemption. Such cases, I urge, are open to exactly the same kind of analysis as cases of preemption in a deterministic setting. With that thought in mind, I set out to provide a unified counterfactual analysis of causation for both deterministic and indeterministic cases, without appeal to chance-raising. In Section 2, I outline an initial sketch for the deterministic case of the theory. The account is a descendant of Lewis's quasi-dependence analysis but expressed in terms of counterfactual embedding. I show how this theory copes with preemption, trumping and over-determination. In Section 3, I broach the vexed issue of the non-transitivity of cause. I accept that cause is not transitive, and modify the theory given in Section 2 to derive the final theory. The overall picture is roughly this: c caused e if and only if c and e occur and had c not occurred a disposition to a causal path issuing in e would not have been manifested in the circumstances. I show in Section 4 how this theory applies to chancy causation.

I argue that a new solution to the semantic paradoxes is possible based on truth-making. I show that with an appropriate understanding of what the ultimate truth and falsity makers of sentences are, it can be demonstrated that sentences like the liar are alethically undecidable. That means it cannot be said in principle whether such sentences are true, not true, false, not-false, neither true nor false, both true and false, and so on. I argue that this leads to a solution to the semantic paradoxes that appears to be free of revenge problems, allows us to maintain classical logic and the validity of the T-schema.