Since Leibniz's time, Cartesian mental causation has been criticized for violating the conservation of energy and momentum. Many dualist responses clearly fail. But conservation laws have important neglected features generally undermining the objection. Conservation is _local_, holding first not for the universe, but for everywhere separately. The energy in any volume changes only due to what flows through the boundaries. Constant total energy holds if the global summing-up of local conservation laws converges; it probably doesn't in reality. Energy conservation holds (...) if there is symmetry, the sameness of the laws over time. Thus, if there are time-places where symmetries fail due to nonphysical influence, conservation laws fail there and then, while holding elsewhere, such as refrigerators and stars. Noether's converse first theorem shows that conservation laws imply symmetries. Thus conservation trivially nearly entails the causal closure of the physical. But expecting conservation to hold in the brain simply assumes the falsehood of Cartesianism. Hence Leibniz's objection begs the question. Empirical neuroscience is another matter. So is Einstein's General Relativity: far from providing a loophole, General Relativity makes mental causation _harder_. (shrink)

I sketch a new interpretation of Malebranche's conception of ideas, thus shedding new light on various of his key doctrines, such as the efficacy of ideas, involuntarism concerning the eternal truths, indirect perception, and vision in God. Briefly, I argue that Malebranche's ideas may be construed as "possible divine volitions," where these are conceptually distinguishable aspects of God, primitively possessed of representational content, by whose exercise God manifests His efficacy. I also defend the claim that Malebranche, in fact, does not (...) subscribe to a "veil of ideas" representationalism, and give two alternative accounts of what he means by saying that we perceive bodies only "indirectly.". (shrink)