Notes on Reductionism

Not counting theology, there probably is no more inherently hubristic academic discipline than philosophy. The “love of wisdom,” as it literally translates, affords the practitioner the salubrious or, depending on your perspective, dubious privilege of sticking his nose into the business of literally every other intellectual endeavor and more than a few that don’t even rise to “intellectual.” Take philosophers of science, for example. Often not scientists themselves, they nonetheless presume to analyze and comment on what it is that scientists, themselves, do, how they go about doing it and what sense or, occasionally, nonsense they speak when they, themselves, talk about what it is they do.

Case in point (by way of the indispensable Arts & Letters Daily), a book review in American Scientist by University of Exeter Professor John Dupré of Darwinian Reductionism: Or, How to Stop Worrying and Love Molecular Biology by Duke University philosopher Alex Rosenberg. Put in its simplest terms, Dupré contends that Rosenberg ascribes to a sort of physicalism termed reductionism, a view that is in general disfavor among philosophers of science although, in one version or another, it is almost certainly the naïve view of most practicing scientists, themselves.

(By “naïve,” I don’t mean to say that most practicing scientists are ill informed or unsophisticated about the nature and practice of science but only that, being practicing scientists, they spend the bulk of their time doing science, not philosophy of science. Similarly, to say of a philosopher of scientist that he is not a scientist is not a way of discrediting what it is that he does (my somewhat caustic introduction aside) so much as a way of putting what it is he does into some sort of perspective. There are, to be sure, philosophically sophisticated scientists and scientifically sophisticated philosophers.)

Part of the problem here, as readers of the linked Stanford Encyclopedia of Philosophy entry will learn, is that both physicalism and reductionism are variously defined concepts. What sort of physicalism and what sort of reductionism one is espousing makes a great deal of difference. Here, anyway, is Dupré’s account of Rosenberg’s position:

[Rosenberg’s] new idea is that recognition of the pervasiveness of Darwinism in biology will enable us to assert reductionism after all. Rosenberg is an admirer of Dobzhansky's famous remark that nothing in biology makes sense except in the light of evolution:

Biology is history, but unlike human history, it is history for which the "iron laws" of historical change have been found, and codified in Darwin's theory of natural selection. . . . [T]here are no laws in biology other than Darwin's. But owing to the literal truth of Dobzhansky's dictum, these are the only laws biology needs.

The suggestion is that something Rosenberg calls "the principle of natural selection" is actually a fundamental physical law. Natural selection, according to him, is not a statistical consequence of the operation of many other physical (or perhaps higher-level) laws, as most philosophers of biology believe. Rather, it is a new and fundamental physical law to be added to those already revealed by chemistry and physics.

Well, maybe. I’ll leave it to Rosenberg and Dupré to fight this one out, commenting only that I suspect most scientists would find it a bit overreaching for a philosopher to assert what is or is not a fundamental physical law, let alone that natural selection counts among them.

Let’s back up a bit. It seems fairly uncontroversial to say that, whatever biology is, its foundation is to be found ultimately in chemistry and, similarly, that whatever chemistry is, its own foundation is to be found, ultimately, in physics. But that is only to say that biological organisms and their component parts are comprised of chemical molecules, themselves comprised of atoms comprised of elementary and sub-atomic particles. That is, after all, what we believe about the material world. Moreover, unless we ascribe, for whatever reason, to an ontology that includes a sort of being or substance other than the material substance of the physical world, we are likewise committed to the view that whatever it is that mental activity and the mind may be must also find its foundation in the material; namely, the brain.

Fair enough. However, what exactly it is that we mean here by “foundation” (my rough term, by the way) is unclear. To be sure, all the evidence points to the notion that human beings are, in purely physical terms, “nothing but” highly complex combinations of elementary particles doing what elementary particles, thus combined, happen to do. We remain a very long way, however, from being able to close all the gaps from here to there and so the question remains, both scientifically and philosophically, whether in principle we shall ever be able to do so. Philosophers’ use of such concepts as supervenience and qualia are attempts to bridge those gaps conceptually even as science attempts to bridge them scientifically.

And, no, I’m not talking about evolution here. Think, instead, the physicist’s understanding of heat as motion and, let's say, an imaginary philosopher's at least facially reasonable question in response whether the proposition "I feel heat" is or must therefore be semantically or logically or referentially equivalent or identical or translatable to the proposition, "I feel motion." Yes, I know I'm conflating the physical phenomenon of heat with the psychological sensation of heat here, something a good (even imaginary) philosopher wouldn't do. What I am groping after, however ineptly, is only that the nexus between the world as science explains it and the world as we experience it is not nearly as straightforward as we are sometimes inclined to believe and that this isn't obviously or simply because science hasn't yet "finished the job."

Science, ultimately, is a human endeavor, an endeavor to understand and explain the world as it is, but such understanding is necessarily human and, as such, necessarily bound by the conceptual and linguistic apparatus of human thought. That is to say, among other things, that science operates within and only within our linguistic, conceptual schema and, as a result, is bound to the limitations, complications and confusions of that schema just as is, analogically, the work of the artist whose representation of the world is necessarily limited by the limits of human perception.

Is, for example, logic, the sine qua non of rationality, a fact about the world or “merely” an incident of human cognition – an accidental fact about how the brain happens to operate? Are elementary particles popping into and out of existence and “action at a distance” aspects of the world as it “really” is or merely necessary posits in our best, current working model of that world? (And what work is “really” doing in that question?) Is what we naïvely - there’s that word again - take to be intentional thought and action necessarily illusory in a world comprised of “nothing but” those particles “randomly” doing their thing, or is some viable sense of genuine human freedom compatible with such a physical world even as human consciousness self-evidently is? Would science itself be possible except in the context of our ordinary and decidedly nonscientific and imprecise language? I think it is clear that the answer to the last question, in particular, is no and, further, that if that is so, it raises all sorts of legitimately philosophical, non-scientific questions about what it is science can and cannot hope to accomplish in terms of affording a complete and consistent understanding of the world and our relationship to it.

I have neither the hope nor the intent of addressing these concerns in detail here, let alone resolving them. (Nor, for now, to argue them in great detail in comments, thanks anyway.) Rather, I want for now simply to point, however obliquely, to several of them and to nudge the reader into considering some of the complications involved in sorting them out. For what it’s worth, my own experience in trying to sort out such questions to my own satisfaction has been that a frontal attack tends not to work very well. Then again, maybe that’s just me. After all, I'm just a guy doing this blog thingie here.

Wittgenstein famously said that philosophy "leaves everything the way it is." (Philosophical Investigations, § 124.) So, I think, does science. It is only we, ourselves, in our better understanding of how things are, that are changed.