To reduce, or not to reduce. That's a stupid question!

I spent yesterday at BU listening to 5 talks on various issues on the relation between philosophy of mind and philosophy of science. While the issue of reductionism came up throughout the day, the three of the five talks were particularly enlightening. The first was by Stephen Horst called "Beyond Reduction: What can philosophy of mind learn from (recent) philosophy of science?" The second was by Michael Silberstein (see my next post for some puppy like slobbering about this guy) titled "Resisting Neo-Scholasticism with Explanatory and Ontological Pluralism in Mind." The third was by William Bechtel titled "Reducing Psychology While Maintaining its autonomy via mechanistic explanations."

The subject of reductionism has always been a bit puzzling to me. It seems to make many people uncomfortable and I can't imagine why. *Of course* everything reduces to physics! Isn't it obvious? (Perhaps the years I spent trying to become a physicist have prejudiced my judgment?) But since yesterday I have seen the light. It isn't that reductionism is false. It is that the discussions of reductionism is a confused mess and it turns out that until now I didn't know what the hell was going on. And I am now very excited to have something to say about the problem.

Reductionism is false--at least a particular brand of reductionism. Reductionism conceived as a language game where we try to translate the vocabulary of a higher science to that of a lower science is not only false, it is just plain stupid! For example, while I think biology reduces to chemistry, I think it is completely absurd to think that we can translate all of the scientific vocabulary of biology into the vocabulary of atoms, compounds and reactions. Even if you take a sub-discipline of biology like molecular biology that is extremely chemically driven, I still think it is hopeless to try to do this kind of reduction. The macroscopic features and phenomena that we are interested are different in kind of those that are the focus of the microstructure. The vocabulary just can't translate. I think this could be demonstrated by considering any fairly simple example and trying to imagine what it would have to look like talking about the macrostructure by only referring to stuff at the microstructure. Does that look like a good translation? I don't think so.

But this language game is not how I have always understood reductionism. I thought reductionism is just the idea that everything that is going on in the macrostructure is caused by/is explained by/supervenes upon the microstructure. And that just seems obviously true to me. I thought the reduction of chemistry to physics just means that all chemical reactions, atomic structures, molecular structures, etc. are explained by how the sub atomic particles interact, and the various forces and laws that govern the world of the small. That is why in a general chemistry class you spend time talking about the electron orbitals and the electromagnetic attractions of ions. What drives chemical phenomena is the physics of particles and atoms. The structure of molecules depends on the subatomic physics of the constituent parts. The same story will go all the way up so that all the phenomena in the natural world supervenes upon that which is going on in the behavior of the tiny parts of the world. It is in this sense that I think everything reduces to physics. But what that doesn't mean is that we can do fluid dynamics just by considering the behavior of the subatomic particles that make up the molecules of the fluid.

I think this somehow relates to the following problem (I think this came from the Mind class)--water is wet. Find me the wet H20 molecules. The molecules themselves are not wet. Wetness is a macroscopic property of a bunch of water molecules that hang out together.

And this leads me to another issue that came up yesterday--ontological pluralism. The first speaker, Steven Horst seemed to have been advocating some sort of ontological pluralism. I think the second speaker, Michael Silberstein might have also been advocating this, but I am not sure. He seemed more focused on the idea of explanatory pluralism which I whole-heartedly endorse. As I understood it, they took the "failure of reductionism" to give them reason to posit entities at the macro-level that are not reducible to entities at the micro-level. And I find this highly objectionable. Just because our vocabulary doesn't reduce doesn't mean the stuff that we are talking about doesn't. What I take ontological pluralism to mean is that the water in the Kinko's mug on my desk has an ontological existence that is distinct from the individual H20 and slummerville sludge molecules that make up the water.

So here is what I think about reductionism. Everything that exists is made up of little subatomic stuff that is governed by the laws of physics. In this sense everything reduces to physics. But even if we had godish-minds that could get over the epistemological accounting problem of measuring and calculating all the little tiny pieces, by hypothesis, we still would only be talking about what happens to individual particles and not their macrostructures. Macrostructures are a higher level of abstraction. And so the vocabulary cannot be reduced. But the further step to taking the things that our irreducible vocabulary refer to as having distinct ontological existence just doesn't make sense to me. The Bechtel talk which focused on reductionism as mechanistic explanations of how the microstructure gives rise to the macrostructure is correct.

So I want to ask this question to those of you who are uncomfortable with reductionism: Do you dislike the claim that the macroscopic phenomena can be explained by the going ons of the microstructure? If you are still uncomfortable with this conception of reductionism, why? What is missing from this physicalist picture?