 While conserved quantity accounts offer an analysis of the notion of being causally related, they do not, on their own, provide a distinction between cause and effect. To introduce the direction of the causal relation, Dowe supplements his conserved quantity account by appealing to Reichenbach’s fork asymmetry (1956). Reichenbach distinguishes forks that are temporally open from forks that are closed. If there is an event C occurring in past that screens off A from B, but there is no screening-off event in the future of A and B, then this constitutes an open fork. If there is an event C in the past and in addition an event \(C'\) in the future of A and B that screen off A from B, we have a closed fork. Now, Reichenbach’s fork asymmetry thesis consists in the claim that all open forks are open toward the future. Dowe (2000: 204) defines the direction of causal processes by the direction of the majority of open forks (thereby, in principle, allowing for the possibility of backward causation). 