Riffing off something Dyke the Elder said in another thread:
Sometimes squirrels feel like a nut; sometimes they don’t. But when they do, they operate uncomfortably close to the boundary between ententionality and intentionality to find one. Within an evolutionary picture, that uncomfortable closeness is about what you’d expect. In a world where there’s a dominant intellectual tradition between human cognition has, for milennia, been set apart from the intelligent interactions with nuts and such by other species, it takes an enormous amount of untangling to get accounts of intelligent interactions that stand up to scrutiny.
No fricking kidding. Last night I was reading the beloved Stanford Encyclopedia’s entry on Mental Causation, and my heart just sank. It felt like a huge mob of philosophers, all jostling and shoving at the entrance to a flybottle. There was almost zero acknowledgement that all of these contortions of logic and all of these argumentative flaws could be set aside simply by rejecting mental/physical dualism. Then, a note of hope at the end (emphasis mine):
One possibility is that truthmakers for psychological truths include irreducibly mental properties. This is not the only possibility, however. Another is that psychological assertions are made true by physical states and properties, states and properties answering to predicates belonging to physics and chemistry. A view of this kind would endeavor to resolve the problem of mental causation, not by tinkering with the causal concept, but by rejecting the idea that mental properties are distinct from physical properties. All parties agree that mental predicates and descriptions differ from physical predicates and descriptions. Application conditions for mental terms and physical terms diverge in ways that preclude definitional reduction of the one to the other. Perhaps it is a mistake, however, to move from this linguistic fact to a substantive ontological thesis: mental and physical predicates designate properties belonging to distinct families of properties.
Whether anything like this could be made to work is an open question. To the extent that you regard the current state of play as unsatisfying, however, it is perhaps a question worth pursuing.
I looked around for more work by Robb and Heil (the article’s authors), and found this paper by Robb which argues that an identity theory (rejection of mental/physical dualism) solves the “exclusion problem” (roughly, that if physical stuff is causally relevant, it would seem to exclude mental stuff from being causally relevant, or vice versa). The fact that an identity theory would solve this problem seems obvious way beyond the need for a paper to defend it, but if you read the paper, you will see that Robb’s main problem is not making sense of his thesis — it’s making sense of his thesis to a community of people whose language for talking about the problem makes his solution difficult to even state.
Here’s an example. Robb is defending a “trope” identity theory (a trope theory is basically a kind of nominalism that says that universal types are really just instances that fall within a similarity class). In the paper, he responds to imagined objections pulled from the literature. One such objection is:
O4: The identity solution merely relocates the exclusion problem. While psychophysical trope identity may rescue the causal efficacy of mental powers (tropes), it still leaves open whether they are causally efficacious qua mental. Put another way: if mental powers are both mental and physical, why not think they are causally efficacious only in virtue of being physical? Closure would motivate this problem, and we’re back with, if not the same exclusion problem, at least very a similar one (Noordhof 1998; Shoemaker 2003, 434; Macdonald and Macdonald 2006, 552-3).
Now think about how you might answer such an objection. I might answer it in the following way:
If mental powers are both mental and physical – if being mental is really just being physical – then talking about them being efficacious “only in virtue of being physical” is either nonsensical or tautological.
I might even add “Duh!” at the end, depending on my mood. But here’s Robb’s response (part of it, actually — the whole thing is too long to quote):
R4: The general thought behind this objection seems to be that we will have solved the exclusion problem only if we finally arrive at something–of whatever ontological category–that’s only mental, that is, mental but not physical. Anything that’s both mental and physical, the thought goes, invites exclusion worries all over again. So, for example, Davidson’s (1980, 1993) desired stopping point is at mental events, which, he says, are physical. But since mental events are both mental and physical, exclusion worries arise, so that we must show that mental events are causes in virtue of their mental features (powers). Similarly, the line goes, if our desired stopping place is with these mental powers, it had better turn out that they’re not also physical, for then we get the same problem all over again, so that we must show that mental powers are causally efficacious in virtue of their mental features (higher-order powers). And so on.
But there’s something suspect in this general line of objection. If psychophysical identity at the desired stopping place continues to invite exclusion worries, why shouldn’t other psychophysical relations at the desired stopping place invite similar worries? Suppose, for example, that mental powers are in fact only mental–that is, mental but not physical–yet are immanent in (Yablo 1997, 275) or nothing over and above (Wilson 2005) the physical, where this may be spelled out in terms of, say, realization (Boyd 1980), the determinable-determinate relation (Yablo 1992), constitution (Pereboom 2002), metaphysical necessitation (Bennett 2008), de re, a priori determination (Jackson 2006), or something else. And suppose that immanence, in whatever form it takes, does in fact secure the efficacy of mental powers with respect to physical effects. Is there still a lingering worry that these powers are efficacious, not in virtue of being mental, but merely in virtue of being immanent in the physical (Lowe 1993, 632-3)? Maybe mental powers are efficacious, but only because they piggyback on their physical base powers. This appears to be, if not the original exclusion problem, one that’s very similar to it.
It could be argued that what Robb’s response here is not substantially different from mine. But what strikes me, in this response and throughout, is that Robb never really abandons the language that distinguishes mental from physical. He is, in effect, trying to make his argument in a foreign language — one ill-suited to the point he’s trying to make. And further, he’s walking into a prevailing conversation that has already rejected his approach. The very first objection Robb cites is:
O1: Psychophysical property identity was undermined decades ago by the multiple realizability argument (Fodor 1974; Boyd 1980; Putnam 1980). Indeed, the contemporary debate is really just about how to save mental causation in the face of the non-reductive physicalism established by this argument. Proposing an identity theory at this point ignores these results and disengages from the contemporary debate.
Maybe that’s what it comes down to. We really want there to be something non-physical. We really want to save a bizarre idea of mental causation, however hobbled and jury-rigged, from the evil forces of non-reductive physicalism. We really want to be special in a way that squirrels can never be.