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)

The pairing argument aims to demonstrate the impossibility of non-spatial objects (including minds) standing in causal relations. Its chief premises are (roughly) that causation requires pairing relations between causes and effects and that pairing relations require spatial relations. Critics have argued that the first claim suffers from counterexamples involving indeterministic causation. After briefly rehearsing the pairing argument and the objection from indeterministic causation, I offer two ways of revising the pairing argument to meet the objection from indeterministic causation.

Interactionists hold that non-spatial objects causally interact with physical objects. Interactionists have traditionally grappled with the puzzle of how such interaction is possible. More recently, Jaegwon Kim has presented interactionists with a more daunting threat: the pairing argument, which purports to refute interactionism by showing that non-spatial objects cannot stand in causal relations. After reviewing that argument, I develop a challenge to it on behalf of the interactionist. The challenge poses a dilemma: roughly, either haecceities exist or they do not. (...) I argue that the pairing argument fails in either case. While the challenge does not explain exactly how the pairing argument goes wrong, it shows that the argument fails. The challenge also explains the difficulty in pinpointing the pairing argument’s failure: exactly how the pairing argument fails depends on difficult issues concerning the nature of objects. (shrink)

This is a book review of Peter van Inwagen and Dean Zimmerman (eds.), Persons: Human and Divine (Oxford: Oxford Univ. Press, 2007).

Many have thought that there is a problem with causal commerce between immaterial souls and material bodies. In Physicalism or Something Near Enough, Jaegwon Kim attempts to spell out that problem. Rather than merely posing a question or raising a mystery for defenders of substance dualism to answer or address, he offers a compelling argument for the conclusion that immaterial souls cannot causally interact with material bodies. We offer a reconstruction of that argument that hinges on two premises: Kim’s Dictum (...) and the Nowhere Man principle. Kim’s Dictum says that causation requires a spatial relation. Nowhere Man says that souls can’t be in space. By our lights, both premises can be called into question. We’ll begin our evaluation of the argument by pointing out some consequences of Kim’s Dictum. For some, these will be costs. We will then present two defeaters for Kim’s Dictum and a critical analysis of Kim’s case for Nowhere Man. The upshot is that Kim’s argument against substance dualism fails. (shrink)

Interactionists hold that minds are non-physical objects that interact with brains. The neural discernment problem for interactionism is that of explaining how non-physical minds produce behavior and cognition by exercising different causal powers over physiologically similar neurons. This paper sharpens the neural discernment problem and proposes two interactionist models of mind-brain interaction that solve it. One model avoids overdetermination while the other respects the causal closure of the physical domain.