Counterfactual accounts of Causation

Counterfactual accounts assert that, if C had not happened, E would not have. That is, C is a necessary condition for E. C can occur without E, but E cannot occur unless C does.

These accounts seem to be the most popular at the moment, but they can get very, very technical and involved.


The most important paper on the subject is Lewis 1973. The postscript to this paper in Lewis 1986a is three times as long as the paper itself, but covers many of the issues arising for such accounts.

Other discussions can be found in Kim 1973, Horwich 1987, and Bennett 1987.


Common Cause

It can be argued that, if C causes both E and F, then if E doesn't happen, that means C didin't happen, so F won't happen either. This means that the counterfactual account gives the wrong answer.


If C doesn't happen, D will go on to cause E, so it is not true that if C hadn't happened, E wouldn't have, so C doesn't cause E. This is also the wrong answer.

Probabilistic Causation

Lewis's account of counterfactuals breaks badly once probabilistic events are allowed in, so that the whole theory has problems.