 Critics of epiphenomenalism can of course point out that there is a property that interactionism, but not epiphenomenalism, assigns to \(P_3\) — namely, the property of being indirectly caused by \(M\).  Epiphenomenalists, however, are likely to think that the intuitive connection between this property and knowledge is much weaker than that between knowledge of \(M\) and the fact that \(P_3\) would not be occurring unless \(M\) had recently occurred. In fact, they may hold that the relevance of indirect causation is exhausted by its ensuring that \(P_3\) would not occur unless \(M\) had recently occurred. They can then reiterate that there is another way of ensuring that this condition holds, namely, the set of relations, diagrammed in Fig. 1, that is affirmed by epiphenomenalism.