Comment on Henry Stapp's Quantum Interactive Dualism
The difficulty with dualism has always been how to specify the interaction between two putatively separate realms of existence, mind and body. Henry Stapp's solution in "Quantum Interactive Dualism", Journal of Consciousness Studies V12 #11, 2005, pp. 43-58 is to connect them via quantum theory, while keeping the mind quite distinct from the brain. The problem, however, is that on Stapp's account the mind itself remains unspecified (like the intelligent designer, not coincidentally) except in terms of ordinary folk-psychological descriptions. Whatever it is, the mind isn't the brain, but beyond that we're not told much about it.
In particular, on Stapp's account we need not ask what determines the mind in its choices: "Thus the 'subjective' and 'objective' aspects of the data are rationally tied together by quantum rules that directly specify the causal effects of the subject's choices upon the subject's brain, without any need to specify the physical antecedents of these choices"; and: "in the quantum treatment the causal connection via the laws of physics is not from the cause of conscious choice to the effects of that choice, but rather directly from the conscious choice itself to its physical effects" (p. 57 JCS, p. 17 pdf ). Why, one wonders, do the causes of choice get such short shrift here? Whatever the reason, for Stapp the mind is causally privileged over the physical brain: the mind drives the brain, but is not itself driven by anything. This renders the mind supernatural; like god, it gets to cause without being caused in turn. Any naturalistic account of a phenomenon has to show its provenance in the natural world, and on Stapp's account, the mind – variously described as consciousness, the observer, the subject's choices, intention, mental effort, William James' "spiritual force", etc. – has no provenance, at least none that he discusses here. The reluctance to address the causes of mind might be related to Stapp's desire to defend a contra-causal conception of free will.
Stapp's discussion is ambivalent about physicalism. On the one hand, he clearly intends to provide a scientifically defensible, naturalistic account of consciousness and its role in choice, but on the other he also says conscious choice transcends physical law. He wears his normal science hat when he says: "Thus the whole range of science, from atomic physics to mind-brain dynamics, is brought together in a single rationally coherent theory of a world that is constituted not of classically conceived matter, bound by principle of the causal closure of the physical, but rather of mind and matter connected in the way specified by orthodox contemporary physical theory." (p. 53 JCS, p. 12 pdf). But orthodox physical theory, although it transcends the classical conception of matter, obviously does not transcend the notion of physical law, the description of which is its raison d'etre. So it can't also be the case, as Stapp (donning his mysterian hat) says elsewhere that "This free choice made by experimenters…is `free' in the sense that these choices are not determined by anything in contemporary physical theory: they are fixed neither by any law nor by any random variables that enter into the theory" (p. 47 JCS, p. 6 pdf). A rationally coherent understanding of mind and matter based in physical theory would have to show how the mind, as well as the brain, is a nomic (that is, law-governed), not mysterious, process. But on Stapp's account there is literally no accounting for choices.
Stapp thinks that explanations involving mental effort or intention are better than merely brain-based explanations, since "the quantum account conforms to specific laws of physics that tie mental events to their causal consequences in the brain in a way that appears to conform to relevant empirical data" (p. 55 JCS, p. 15 pdf). But unless explanations involving mental effort and intention can state clearly where these originate – what their causal antecedents are – then we really haven't explained anything when it comes to human choice and behavior. Stapp admits that "incentives lead to effort", but this suggests that mental effort is caused; it belies his earlier assertion that choices aren't governed by any law-like regularities, so he can't go too far down this path. Instead, the intervening variable of categorically mental effort is left unaccounted for, as it must be if we're trying to rescue contra-causal free will.
TWC - originally posted to JCS Online, Dec 7, 2005