  A second version of the Problem of Interaction is the “Pairing Problem” (Kim 1973, 2005; Sosa 1984; Foster 1991, ch. 6). Imagine two exactly similar minds M1 and M2 and the bodies B1 and B2 to which they are “attached”, that is, the bodies with which they directly interact. In virtue of what is M1 causally paired with B1, and M2 with B2?