  Autonomy solutions can make it appear that the causal powers of mental properties “float free” of their physical realizers, bringing to mind the doctrine of parallelism (for replies, see Thomasson 1998; Marcus 2001, §3.3). Some non-reductive physicalists have accordingly looked to tie the causal powers of mental properties more closely to those of their physical realizers. The idea is that mental properties are so intimately related to their realizers that the former “inherit” the causal powers of the latter. The relation between levels is not one of rivalry, such that the physical might exclude the mental, but one of cooperation. Nor, moreover, does there seem to be any threat of overdetermination, since the mental works through the physical. (Compare the metaphor of “transparency” in Jackson 1996.)