Causation - The Asymmetry Of Causation Through Causal Connection

Two variables A and B are "causally connected" if either A is a cause of B, B a cause of A, or a third variable causes them both. If causation is transitive, then it turns out that everything causally connected to X is connected to its effects, but not everything connected to Y is connected to its causes. When X → Y, everything causally connected to X is causally connected to Y (Fig. 7a), but something causally connected to Y is not necessarily causally connected to X (Fig. 7b).

Figure 7. The asymmetry in the transitivity of causal connection
SOURCE: Courtesy of the author