Dualism

I’ve lifted this from the comments section of this as I found the question raised interesting and it got me thinking. The comment, nor surprisingly, comes from Mark Johnson. It asks, in effect, what the consequences of Chomsky’s observations concerning classical dualism and its demise are for studying how brains incarnate minds? In his own words:

I'm not sure I'm correctly understanding C's point about Newton destroying Cartesian dualism by destroying a purely contact-based mechanistic world; we all now believe in non-contact based forces like gravity. Is the point that we should stop worrying about how mental phenomena are instantiated in the brain, and just accept them as mysterious primitives?

This got me thinking: say Chomsky’s history is right (and I think he makes a good case for it being so) what’s the take home message for us. Here’s what I replied”

You ask a good question. Here's how I understand things. The most important consequence of the dissolution of the classical mind/body problem is what it says about how unification is to proceed. In the classic version, we KNEW what physical forces HAD to be: contact mechanics. Thus, unification meant reduction to physics as we know the limits of physical explanation. Once we give this up, we don't actually know the "limits" of the physical; after all, if God can link gravity, an occult property to matter, then she can link anything to matter. Thus unification can go either in the direction of reduction or in a more roundabout way by changing the "reducing" science and leaving the "reduced" one more or less as is. This is exemplified by Chomsky's discussion of chemistry and physics. The classical mind body conception privileged physics and required that every other science march to its tune. With tis demise there is no preferred direction of unification: either the physics changes or the chemistry or both.

So, no there is what has been called Broca's Question in language: how do brains realize minds. But with the demise of the classical mind/body conception there is no reason to believe that the neurologists have it right and the cognitivists have it wrong when the two clash. The way I see it, what C is saying is that after Newton, the scientific playing field has been conceptually leveled.

This also has a practical implication: it is critical to develop "bodies of doctrine" within a discipline as well as figuring out how to unify across them. And these bodies of doctrine must be taken seriously. So, if you want to exlain how brains do language, then you need to explain how brains to the kinds of things that linguists have discovered over the last 60 years. This stuff has an integrity and counts intellectually even if there is no Nobel Prize in cognition. In reading much of the neuro literature there is this sense that the important big shot science is neuro and mental matters must just toe the line when the two appear to be in conflict. This is a residue of the dualism that Newton exploded. C's point is that this posturing has no scientific merit anymore, as we just don't know the limits of the physical/neurological.

That's how I see it.

I want to invite comments on this for I believe that it is important. Let me say how.

An important theme in Chomsky’s philo/methodological writing has been that though classical dualism has been discredited and nobody alive today wants to admit to being a dualist, a kind of methodological dualism is currently alive and well and very widespread.  Even more oddly, its chief practitioners are exactly those who go around telling us confidently (and often and loudly and in a self congratulatory tone) “There are no ghosts!” And if you don’t believe that minds are just brains at some other level of description (e.g. “You know, you can cut the mind with a knife!) then you are a religious nut who also likely sticks pins into doll effigies of your enemies.

I confess that when so assailed I am generally inclined to ask what’s so wrong with dualism? Or more correctly, what evidence is there that minds are reducible to brains?  I even once asked this of Vernon Mountcastle (a big shot neuro person who Chomsky mentions in his piece) and he replied roughly that there are no ghosts or souls and so that must be the way it is. He conceded that he had no idea how that could be, but it was clear to him that it was this way as any serious person would see because were it not so we’d have to all believe in ghosts. In short, the untenability of dualism is taken as an obvious corollary from the non-existence of ghosts/souls. Who knew? Say that we never managed to unify chemistry with (a much revised physics), would that have implied ghosts as well? Say that we never manage to unify quantum mechanics and relativity, what would that imply other than we don’t know how to put them together? But for some reason, our failure to unify mind with brain is taken as a singular failure with cosmic sociological and spiritual ramifications.[1] And this is a manifestation of a contemporary dualist mind set. How does it get expressed?

It shows up in various guises: the belief that cognitive/linguistic findings must dance to the biology’s/neuroscience’s/CS’s tunes, that behavioral studies are fine but brain measures are where truth lies, that findings in linguistic are suggestive but those in neuro-science are dispositive, the belief that if there is a conflict between linguistics and evolutionary biology then the lack of reconciliation is a problem for the former but not the latter, etc. Chomsky has rejected all of these sureties, and, IMO, rightly so.  What Mark’s comment made me see more clearly than I had until now is that these convictions are actually the distorted reflections of a discredited dualism and so are not only illegitimate but are actually the modern incarnations of the positions they claim to be dismissing.  Here’s what I mean.

Classical dualism, as Chomsky noted, had a criterion of physical intelligibility. If the explanation was not “mechanical” then it was either occult (i.e a vestige of the old discredited Aristotelianism) or trivial (e.g. sleeping pills induce sleep because they have dormitive powers). Descartes accepted this view and suggested that in light of this there had to be a second substance, res cogitans, in addition to res extensa (i.e. matter) and that the different two substances that could not be unified (though they did mysteriously come to interact in the pineal gland!). Note, that this conception allows for the possibility of two distinct sciences; a science of the physical and one of the mental, both potentially quite interesting though fundamentally incapable of unification. What Chomsky points out is that with Newton’s undermining the mechanical world view, we lost the criterion of intelligibility that it underwrote (i.e. with Newton’s physics based as it was on forces inherent in matter that could act at a distance, the criterion of intelligibility was discredited). This had two consequences: first, ‘material’ came to mean ‘whatever the physical sciences studied’ (i.e. there was no intelligibility criterion imposed on physical possibilities) and the idea that minds and matter must be different no longer held (see Chomsky’s quote of Locke wherein Locke says that if God can put gravitational attraction together with matter then s/he can also pack in mental properties if s/he so desires).

In fact with the demise of the “mechanistic” criterion of physicality, there is no a priori limit on what counts as a physical property and this is important. Why? Because this means that there is no fixed point in unification. What I mean by this is that in unifying A and B there is a priori reason for privileging the predicates of one over those of the other. Another way of saying this is that there is no longer any reason to think that unification will proceed via reduction, reduction being where the reducing theory is held to be epistemologically privileged and the predicates/laws of the reduced theory required to accommodate to those of the reducing one. Moreover, not only was this a conceptual possibility given the demise of classical dualism, but, as Chomsky noted, this is what in fact took place with chemistry and classical physics (the reducing theory changed from classical to quantum mechanics) and Gallistel noted is what occurred with classical genetics and biochemistry (i.e. the former stayed more or less the same and the latter had to be radically rethought).  This, I believe, is an important methodological lesson of Chomsky’s exposition.

Importantly, this moral has been lost on our modern dualists. Or more accurately, many contemporary scientists have misunderstood what the demise of dualism amounted to and have resurrected a methodological version of it as a result. Those in the “harder” science think that their theories do enjoy epistemological privileges. The demand, for example, that linguistics must respect current theories of brain architecture (e.g. connectionist) to be legit (rather than drawing the conclusion that linguistic insights call into question these theories of brain architecture) is an instance of this. Because these scientists understand unification in terms of reduction they take the to-be-reduced-theory/domain to be conceptually less well grounded (more epistemologically suspect) than the reducing one. And though this made sense under the classical dualist conception, it no longer makes sense now precisely because we have abandoned that which lent “materialism” its privileged place (viz.  the doctrine of physical intelligibility).

There is a moral in all of this. Two in fact.

First, that the body of doctrine that we have developed in linguistics over the last 60 years requires explanation. The fact that it’s an interesting question how brains incarnate FL does not mean that putative facts about the brain discredit the facts that we have unearthed. Indeed, we should insist loudly and on every relevant occasion that a theory of the brain will be a good/complete one just in case it finds a way to incorporate the facts that linguists have uncovered. If these don’t fit into our currently favored neuro theory of the brain, then this is a problem for the brain sciences at least as much as it is a problem for linguistics.

Second, Chomsky has identified the source of the bullying; it comes from misunderstanding the history and import of the mind/body problem. There is an interesting question that all agree would be great to crack (i.e. Broca’s Problem: how minds live on brains or how to unify thought and neural structure) but this agreement does not privilege either term of the unification relation. And anyone who thinks otherwise is a closet dualist. Say that next time you are bullied and stand back and watch the fun. 

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[1] I should add that I don’t believe in ghosts but I don’t see this meaning much. It seems to me entirely possible that we will never really know how minds live on brains. It’s certainly the case that most of the hard problems in psychology (e.g. consciousness, free will, all things considered judgments) are as ill understood today as they were when Descartes first took them as evidence for a distinct mental substance. Indeed, Mountcastle agreed and said so in his lecture. So his anti-dualism is an expression of faith, rather than a conclusion of argument or inquiry. I have nothing against such ambitious goals. But ambitious goals should not be confused with established conclusions. Wishing does not make it so.