Questions: Counterfactual Theory of Causation

Question 1

Event C caused event E on Lewis's original counterfactual analysis. What does this mean?

• A. C and E are regularly conjoined across similar situations
• B. In the closest possible world where C does not occur, E also does not occur
• C. There exists some possible world where C occurs and E does not occur
• D. C is a necessary condition for E in all possible worlds

Answer: (B)

Lewis's analysis requires counterfactual dependence in the *closest* possible worlds — those that differ from actuality only minimally in the absence of C. Option C is too weak (just any possible world); option D is too strong (necessity across all worlds); option A describes the regularity theory, not Lewis's account. The key move is using proximity among possible worlds (similarity to actuality) to evaluate what *would* have happened.

Question 2

Why does the case of early preemption pose a problem for Lewis's original counterfactual theory?

Model answer: In early preemption, two potential causes C1 and C2 are both headed toward E, but C1 fires first and produces E before C2 can act. The problem: in the closest possible world where C1 is absent, C2 would have taken over and produced E anyway. So E does *not* counterfactually depend on C1 — remove C1 and E still occurs (via C2). But intuitively, C1 caused E. The theory thus fails to identify the actual cause in such cases, returning a false negative.

Lewis attempted to handle this through chains of counterfactual dependence and later through his 'influence' account. The deeper lesson is that counterfactual dependence (if C hadn't happened, E wouldn't have happened) is neither necessary nor sufficient for causation in complex cases — it is a good indicator in simple, isolated cases, but the metaphysics of causation is harder to capture in a single clean analysis.