The Direction of Causation

Abstract

The problem of the direction of causation can be discussed on two levels. We can wonder if it is in every sense necessary that a cause precedes its effects. But we can also-on a more uncommitted level-ask the following question: Whether or not retroactive causes are real or conceivable phenomena, can we put into brackets the temporal order of two events and still decide which one is cause and which one is effect? Now, evidently, if one answers the first question in the negative one has to face the second one. But this one could also be put forward in its own right. Even if it should be a necessary truth that a cause precedes its effect(s), it might be possible-and clarifying-to explore other ways of making sense of the cause-effect distinction. It is in this perspective that this article primarily should be read, since I will make no positive case for the possibility of retroactive causes. On the other hand, since I contend that a clarifying account can be given of the cause-effect distinction, independently of relying on the temporal order of two events, the article might also be read as a prolegomenon to a discussion of the possibility of retroactive causes. To accept that a causal process has a direction seems tantamount to accepting that it uniformly flows from cause to effect. It could not possibly flow in the opposite direction. One way of giving an initial precision to this idea of an asymmetrical causal direction is to say that it is the cause which by necessity explains the occurrence of its effect-in the sense that we would never consider a the cause of b if we maintained that b explained the occurrence of a. But of course, connecting the distinction between cause and effect with that between explanans and explanandum cannot be of any great help in really clarifying the first distinction. That an event explains the occurrence of another event amounts to little more than a mere verbal paraphrase of saying that the first one is the cause of the second one. Let us, however, ask a somewhat different question: How do we explain