The paper contains a novel realist account of causal production and the necessary connection between cause and effect. I argue that the asymmetric relation between causally connected events must be regarded as a product of a symmetric interaction between two or more entities. All the entities involved contribute to the producing, and so count as parts of the cause, and they all suffer a change, and so count as parts of the effect. Cause and effect, on this account, are two (...) different states of the very same compound substance, or system, one coming to exist out of the other. (shrink)