Is Functionalism Physicalism?

March 9, 2007

How does functionalism relate to physicalism? This isn’t a trivial question and this post is just to raise the issue rather than attempt to solve it. One of the things at stake is, if philosopher x is a functionalist and y an opponent, then if they have different definitions of what functionalism is, how they disagree will be less clear.

Ned Block and Jerry Fodor are broadly functionalists save for qualia and some higher cognitive functions (Fodor) while just assuming physicalism is probably true. So for instance, while the inverted spectrum argument is ofted wielded against physicalism, in the case of Block and Fodor, it targets only functionalism. And if functionalism in a strong sense is false but physicalism true, how are they different?

David Chalmers whose key interest is narrowly the ontology of mind, virtually interchanges the terms functionalism and physicalism. He argues the world is causally closed and that everything save conscious experience reduces to the physical. More specifically, he argues that the soft sciences are ultimately linked to the physical by their functionalizability. If something is functional, then it’s physical. How the micro world could specifically be understood on functional terms is unclear, but paragraphs like this are key:

“2. The principle of organizational invariance. This principle states that any two systems with the same fine-grained functional organization will have qualitatively identical experiences. If the causal patterns of neural organization were duplicated in silicon, for example, with a silicon chip for every neuron and the same patterns of interaction, then the same experiences would arise.”

So for him the “causal patterns of neural organization” is the same thing as the “fine-grained functional organization”. He notes later in the paragraph Searle’s disagreement, but where does Searl disagree when his own view champions “causal supervenience?” What is the difference between “causal supervenience” and “causal patterns of neural organization?” I think Searl believes if silicon or biology can truly duplicate physical causality in the right way, then consciousness results. But then, there is no equating for Searle causality with functionality. To sharpen my point here, consider Searle’s rejection of Penrose’s quantum account of mind. Searle affirms that the brian is 1) just a machine 2) a neural net. But isn’t that just what the functionalists have been trying to tell Searle all along?(!)

Not exactly, because the causal account of how that machine IS a machine matters. Modeling the synaptic connections perfectly is for Searle, still just a model. But isn’t Chalmers model going deeper than that? Herin lies where I think they’re talking past each other. At what point are we moving from a functional model to the real thing? When Chalmers says we’ll replace a neuron with a chip performing the same function, he seems to mean, down to the relevant level of physical causality wherever that is. And when Searle rejoinds, he seems to mean, a functional account can’t capture the relevant causal level. Chalmers assumes functionalism is physicalism, and Searle assumes it’s not.

Searle argues that functions are something we ascribe. Is there anything inherently “computational” about an abcabus (someone please tell me how to spell that word)? It’s a kids toy or a door prop as much as it is a calculator depending on how we interpret it. Whereas it would seem there is something more objectively real about physical causality. Now I don’t think that ultimately works because I think that physics is also a product of our interpretation. And more importantly, some of Searle’s more ambitious attempts to trivialize functions (that can be “anything”) have been adequately refuted.

Needles to say, I think Searle and Chalmers are both right in their deeper points. But the whole discussion is problematized by the lack of agreement on what functionalism actually is, and particular, how it relates to physicalism.


Supervenience and Reductionism

January 25, 2007

In a previous post I noted that supervenience is probably the most popular conceptual tool used to explore the ontology of mind. The notion was introduced into mind by Donald Davidson who had a very interesting solution to some of the vexing problems of the time. I won’t go into that here, but let’s just say the target for him was to keep the universe sane, only exhibiting a single personality, while at the same time getting out of causal reduction. Supervenience allows us to see a way in which everything must be, in this case physical, without pressing the issue as to how it accomplishes this. It’s kind of like, I can see that Jones is clearly guilty and can clearly place him at the scene of the crime, even though I don’t have the slightest idea how he accomplished it.

 The bankrobbery supervened on Jones, his mask, cloak, and bag of tools caught clearly on tape. But how he cracked the safe is an utter mystery.

 While a great tool to explore the idea of physicalism with greater precision, it’s not universally accepted as having the ability to accomplish the goal of monism without reduction. J. Kim in particular makes a strong case that physicalism ultimately can’t survive absent causal reduction.


January 16, 2007

“Naturalism” is another one of those tricky words. I don’t think it’s nearly as an important a notion as “physicalism” for the philosophy of mind, but it does come up and I mentioned it in passing in the last post. It’s possible, apparently, to be a naturalist without being a physicalist. I’m thinking of course of David Chalmers here who claims that mind is something fundamental to the way the universe is, like a fundamental law of physics, but something yet different.


January 15, 2007

One of the interesting things about the philosophy of mind is that the object of study, the human mind, is so troublingly complex and mysterious that it’s the one corner of the intellectual world where perfectly serious naturalists are tempted in the direction of dualism, or rather, the rejection of physicalism. Dualism is the belief that there are either multiple things, or properties, that constitute the world. Physicalism is the belief that everything ultimately is constituted of one kind of thing, loosely, the stuff physicists study.

It would be fascinating, baring the remote possibility some religion or another happens to be the way things are, the universe seriously can’t ultimately be understood entirely in terms of physics.

From the outset, for those who are new to studying these issues, a couple things need to be set straight with regards to physicalism. A friend of mine once said, “Everything is physics, but physics isn’t everything”. Physicalists understand that there is beauty in the world, they aren’t trying to rain on anybody’s parade by turning everything into equations – even if that’s ultimately possible. Beauty, politics, and economies are understood at a higher level than subatomic particles. But ultimately they depend on the physical – in fact, they are entirely constrained by the physical.

In mind, the language to broadly talk about the physical isn’t in terms of reductionism but a dependence relationship – supervenience. If A supervenes on B, then no changes can be made in B without resulting in a Change in A, and usually vice versa. So in other words, even though we don’t have an account of how the beauty of a sculpture reduces to particles zipping around in a vacuum, we know that the beauty is constrained by those particles. We have a hard time imagining how two identical works of art in every way, including cultural context and history, could differ in their beauty. So while there are many high level features of the world that are inexplicable in terms of reductive physics, we still can see how to retain a minimal statement of physicalism in a dependency relationship.

But some philosophers, without religious convinction, belive that the mind escapes being a mere high level property and ultimately isn’t something that supervenes on the physical world. Philosophers who reject this view, which is probably most of them in the end, would I think admit that understanding the mental in terms of the physical isn’t a straightforward victory.