 Counterfactual dependence has also featured prominently in theories of mental content, which explain how a mental representation like the concept dog comes to represent dogs. Informational theories take their inspiration from natural representations like tree rings, which represent, in some sense, how old the tree is (Dretske 2011). While some accounts in this family are called “causal theories of mental content”, it is somewhat limiting to formulate the view as: X represents Y just in case Y causes X. Even for the tree rings, it is metaphysically controversial to claim that the tree rings are caused by the age of the tree, rather than thinking they have a common cause or are merely causally related via a number of laws and factors, e.g., rainfall, seasons, growth periods. For this and other reasons, Dretske (1981, 1988, 2002) formulates the relationship in terms of conditional probabilities: