Saturday, May 24, 2008

Gould: Pluralism by monism

Well, I saw that Ryan Gregory mentioned this blog on Genomicron, giving me the “Gregory Bump” (that makes the most sense to fans of the Colbert Report). So, I figured I should add something of substance to my blog, which I haven’t done in a while – we’re still in session here at UCSB, on the quarter system. Here ‘tis, for what it’s worth:

One of my life goals is to have an original idea – since I’m an evolutionist by passion, it’s difficult, because Darwin has already claimed most of the original ideas in my field. But here is an insight I’ve had that might be somewhat original. The field is history of science, so that explains why Darwin didn’t already think of it. History of science is also not my field, which could explain my perception of novelty: Chances are someone already thought of this, and I just don’t know it, because it’s outside my field.

The idea, in a phrase, is that the controversial evolutionist, Stephen Jay Gould, practiced “pluralism by monism”. This is a fun idea in many ways. First, I’ll explain in a little more detail what I mean by “pluralism by monism”. Then I’ll explore some of the fun implications and ironies of this idea.

Basically, as eloquently presented by Michael Shermer in “In Darwin’s Shadow”, Gould (like many great scientists), pursued deep philosophical themes that permeate western thinking, and all of science. Shermer named several “thematic pairs”, such as theory versus data, contingency versus necessity, punctuationism versus gradualism, etc. I won’t go into here what all these mean, in detail, but the general idea is that these are opposing concepts that color how people view the world. I like to think of them in light of the Taoist philosophy of the “unity of opposites”. One cannot fully understand one concept without understanding it’s opposite. Opposites are in fact one thing, two sides of a single coin, that grade into each other, yin and yang. Pluralists, then, are those who see both sides of the coin, those who see the unity of opposites, and see the falseness of dichotomies.

My thesis here is that Gould tried to elicit pluralism in the field of evolutionary biology by taking a monistic stance that opposed most of the field. He would find cases where the field had gone too far to one side of a false dichotomy, and bravely, forcefully, and egotistically argue for the exact opposite. If evolution was all about arguing for yin – Gould would stand up, and say, “what about yang?” His ego was large enough, and his intellect sharp enough, that he believed (and often achieved) that he could bring the entire Force into balance by going – often alone - to the Dark Side.

Perhaps some explicit examples will help. Let’s start with Shermer’s pair “Adaptationism – Nonadaptationism”. The field of evolution pre-1979 had skewed toward Adaptationism, leading Gould and Lewontin to coin the phrases “adaptationist program” and “Panglossian Paradigm” (all for the best). T. rex’s reduced limbs were adapted for titillating females, Aztec sacrifice and cannibalism were adaptive for a protein shortage, and architectural spandrels were adapted as an artist’s canvas. There was a disturbance in The Force - it was in extreme imbalance - until Gould and Lewontin stepped over to the Dark Side to try to restore balance. It’s not all adaptive, they said, there are constraints, historical and structural, and most of all we cannot simply assume something is adaptive before testing it.

When I mention Gould to some of my colleagues (who lean toward being adaptationists, as far as I am concerned), they loathe Gould, saying he was against natural selection (adaptationism). To some, he was a monist on this issue, taking a stand against natural selection. Not at all, he knew the strength and frequency of natural selection. He was only arguing for pluralism.

Another case in point is Shermer’s punctuationism versus gradualism. The field of evolution was focused only on excruciatingly gradual modes of evolution, explaining away other patterns, like phenotypic gaps in the fossil record, as missing data. In response, Eldredge and Gould proposed punctuated equilibrium. They argued that stasis and discrete jumps are a common mode of evolution, such that the fossil record might more often be an accurate record of the evolutionary process than once appreciated. Here again, the field had gone too far to one side of a false dichotomy. Punctuated equilibrium acted as a pull toward a more central tendency that considered other modes, besides pure gradualism. Again, taking a contrary stance inflamed some people (for example, Punctuated Equilibrium is sometimes referred to as "Evolution by Jerks".)

A final example that I will mention here was aimed at humankind more than at the field of evolution. Humans have long held the view that our species is a pinnacle. Either humans are specially created in the image of God (e.g. perhaps She looks like Whoopi Goldberg). Even after Darwin introduced the idea of global common descent, and tree thinking, many people still shoehorned humans at the top of a ladder of progress (see my post Iconography of an Expectation). The key dichotomy here is “contingency versus determinism”. Many people think of human evolution as destined, determined either by the supernatural (think Whoppi) or the natural progression of evolution gradually increasing complexity until the summit of human perfection was achieved. Enter Gould’s Wonderful Life (and similarly themed short essays), where SJ entertained the mostly monistic thesis that contingency dominates the history of human and in fact all evolution. Replay the tape of evolution (an interesting linear, non tree-thinking analogy) and humans only evolve one out of a trillion times. Nothing special about us, just dumb luck; we’re just lucky to have been part of one of the clades that survived a decimation after a Cambrian Explosion. By taking this stance, Gould could take on religious fundamentalists and wrong-headed evolutionists in one fell swoop aimed at putting paleontology at the center of a new revolution in human understanding.

The fun part of this idea is the irony. Achieving pluralism through monism seems impossible. Yet at the same time it highlights the theme of false dichotomies so deliciously. There can be no pluralism without monism, just as we cannot understand adaptationism without understanding what is not adaptationism, etc. All this highlights the philosophical underpinnings of evolutionary biology. Rather than being built upon fundamental laws, natural history presents myriad possibilities, forcing arguments about what is most important. Echoing this sentiment, I’ll end with a quote from Gould and Lewontin (1979):

“In natural history, all possible things happen sometimes; you generally do not support your favored phenomenon by declaring rivals impossible in theory. Rather, you acknowledge the rival but circumscribe its domain of action so narrowly that it cannot have any importance in the affairs of nature. Then, you often congratulate yourself for being such an undogmatic and ecumenical chap."


TR Gregory said...

I think this is very sensible, and in fact one can see how it would be reinforced, as those who took side A would try to argue that Gould's side B was, in fact, unimportant -- making Gould emphasize side B more forcefully.

Joshua said...

Very nice post. An interesting insight. We humans tend to be very polar in our opinions. False dichotomies abound!

Thanks to tr gregory for pointing out your is now part of my google reader feed.

Mike the Iron Stomach said...

Excellent entry. That is why science is so beautiful: it's dynamism. It operates on a system that does not automatically preclude differing views. Status quo may push against differing views, but the evidence-based mechanisms of the scientific method eventually prevail, and allow the knowledge to push forward.

I agree with Joshua's comment, excellent insight. This "pluralism by monism" could apply to much more than science, I'm sure.

David Berger said...

I'm not a biologist, but I've read my share of Gould (including the "Spandrels" paper), and I tend to agree with his critics. You hit the nail on the head with your discussion of false dichotomies, but it seems to me that Gould often promoted false dichotomies in order to sell his ideas as revolutionary.

You mention adaptationism, gradualism, and "determinism". Richard Dawkins, in "The Blind Watchmaker", presented versions of these ideas that are different from Gould's--more subtle, more sensible, and, according to Dawkins, more closely resembling what most biologists actually think. To my knowledge, Gould never addressed any of them.

But again, I'm not a biologist, and I could be a decade or two behind the curve. I found your blog through Pharyngula, and I look forward to your next post.

Todd Oakley said...

You raise a valid point. Many people accuse Gould of making caricatures of the opposing arguments. I think he did tend to over-estimate the "monism" of the opposing arguments sometimes. Yet the Spandrels paper for one does address that criticism, whether it answers the criticism or not is a judgment call. In any event, your point is well taken.