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A new argument for theism has been making the rounds: the argument from psychophysical harmony. This argument is put forward by Cutter and Crummett in a forthcoming article in Oxford Studies in Philosophy of Religion, but you can find the article here.
Cutter and Crummett have been making several appearances to discuss this argument. While I do not find the argument convincing, I am enthusiastically in favor of proponents of philosophical views actively seeking a wider audience. You can see these discussions (in chronological order) here, here, here, and here.
Psychophysical harmony is the purported fact that there is a correlation between phenomenal states and physical states. This correlation is purportedly surprising, and calls for an explanation. Naturally, those accounts which do a better job of explaining the correlation should be favored to the extent that they are able to do so, relative to competing accounts which are less capable (or incapable) of explaining the correlation.
According to the proponents of this view, psychophysical harmony spells trouble for a variety of views, including moderate physicalist views (type-B physicalism). Proponents of this argument appear to believe that, because the argument puts pressure on type-B physicalism, we (at the very least) ought to reject type-B physicalism. This is supposed to move us towards theism.
However, there is another option available to us when confronted with a shortcoming with moderate physicalism: embrace a less moderate form of physicalism, i.e., type-A physicalism. Type-A physicalism offers a straightforward response to psychophysical harmony: there’s no such thing as psychophysical harmony, because there’s no such thing as phenomenal states.
Unfortunately, such views are dismissed out of hand by Cutter and Crummett, who state in their forthcoming paper:
We will assume, with most physicalists nowadays, that whether or not there is an ontological gap between physical/functional truths and phenomenal truths, there is at least an epistemic gap. In other words, scenarios in which phenomenal truths vary independently of the physical/functional truths are a priori epistemic possibilities, even if these don’t correspond to any metaphysically possible scenario
However, the quality of an argument is at best only as good as the assumptions behind it. And in this case, I don’t grant this assumption, and don’t think we should. More importantly, nothing about the argument requires that we set aside type-A physicalism. Why not instead present the argument in a way that explicitly acknowledges one’s options: to (a) accept that psychophysical harmony is a legitimate problem, and then consider how well competing accounts can address it or (b) keep open the possibility that there is no such thing as psychophysical harmony. This strikes me as a better way to frame the argument, since it leaves open the primary avenues of response to the argument. One could then append one’s argument by saying that one doesn’t think (b) is a viable option for easons extraneous to the argument.
“Thus, we assume the falsity of so-called “a priori” (or “type-A”) physicalism, the view that physicalism is true and there is not even an epistemic gap between the physical truths and the phenomenal truths.
One reason I don’t think the authors should dismiss this view as false appeals to a phrase that seems to have been trite from the very moment it was first used, but is nevertheless a valuable precept to keep in mind: One philosopher’s modus ponens is another’s modus tollens, a phrase helpfully immortalized by Williamson (2022) in an article titled, “One philosopher's modus ponens is another's modus tollens: Pantomemes and nisowir.”
When confronted with an argument, one can deny the conclusion, and reason backwards that at least one of the premises must be false. As Williamson puts it:
That one person's modus ponens is another's modus tollens is the bane of philosophy because it strips many philosophical arguments of their persuasive force. The problem is that philosophical arguments become mere pantomemes: arguments that are reasonable to resist simply by denying the conclusion. Appeals to proof, intuition, evidence, and truth fail to alleviate the problem.
Why do I mention this? Because psychophysical harmony purportedly creates problems for type-B physicalism that can be solved if one abandons this version of physicalism in favor of theism.
So long as we are willing to reconsider type-A physicalism, however, we could tollens where one might have gone for a ponens. That is, when confronted with an argument that appeals to the existence of psychophysical harmony as one of the premises, and concludes with the truth of theism, we might think to ourselves: well, theism is false, so if accepting psychophysical harmony would lead us to theism, then perhaps we should reject psychophysical harmony. In other words, if psychophysical harmony leads to theism, rather than accepting both psychophysical harmony and theism, we can reject both, and one way to do this is to endorse type-A physicalism.
I already endorsed type-A physicalism before encountering this argument, so what’s presented as some kind of super serious philosophical problem simply never was a problem for me to begin with. One would have thought that this is to the credit of type-A physicalism: isn’t it a good thing if a particular position doesn’t suffer from a serious problem? So why is it dismissed? Presumably for reasons unrelated to the argument for psychophysical harmony
(usually the objections to type-A physicalism that I’ve seen consist of little more than claiming that it’s obviously wrong or claiming that one has intuitions or phenomenology that suggest that it’s false. These are terrible objections, but that’s typically what people go with. An equally common reaction is incredulity. I take it readers are aware incredulity isn’t a substantive objection. I’d be incredulous if you didn’t).
This move won’t appear available to us if we already rejected type-A physicalism. It seems like Cutter and Crummett have preempted this possibility by assuming the falsehood of this view. That type-A physicalism is false isn’t a feature of their argument, nor is the probability that it is false elevated by their argument; if anything, their argument increases the plausibility of Type-A physicalism. Rather, we were faced with three competing options:
(1) Theism
(2) Type-A physicalism
(3) Type-B physicalism
If it turns out Type-B physicalism does a bad job of explaining psychophysical harmony, but theism does a good job of explaining psychophysical harmony, this should reduce our confidence in type-B physicalism.
However, rather than only increasing our confidence in theism, problems for type-B physicalism could prompt us to reconsider type-A physicalism. In other words, if we are deciding between (1)-(3), considerations that count against (3) can increase the plausibility not just of theism (1), but Type-A physicalism (2).
In short: Both type-A physicalism and theism provide a solution to the supposed problem of psychophysical harmony: one by accounting for it, and one by denying its existence altogether. If type-B physicalism can’t account for psychophysical harmony, it’s not obvious we should
(a) Conclude that psychophysical harmony is real and that theism is true
(b) Conclude that psychophysical harmony isn’t real and that type-A physicalism is true
Whenever we’re confronted with an argument, we can go for a tollens instead of a ponens. Williamson encouragingly refers to this as “the bane of philosophy.” I say “encouragingly” because I like the idea that my response to an argument would be regarded as a bane of philosophy. That has a nice ring to it.
References
Williamson, J. (2022). One philosopher's modus ponens is another's modus tollens: Pantomemes and nisowir. Metaphilosophy, 53(2-3), 284-304.
I don't see why psychophysical disharmony would be a problem for type B materialism. The relationship between the phenomenal and the physical can't vary from token to token, when token identity is true, so the psychophysical relationship must be consistently wrong if it's wrong at all...but why would that evolve?