21 january 2005
physician, heal thyself (part I)
Or: the peril of writing beyond your knowledge.
Once upon a time, when I was still a graduate student in physics, I was at dinner with some colleagues and their significant others. During the meal the question arose of why we had chosen that particular discipline. My response was that if I could get a PhD in physics, it was prima facie evidence that I could have gotten a doctorate in any other field. This did not set well with the only non-scientist in attendance (or with her tamed boyfriend).
I jumped ship before attaining the PhD in that discipline. And although I've since learned better, at one time I did honestly believe the claim made at the dinner party. To some degree, it was learned chauvinism: during the twentieth century, physics was queen of the sciences, and nobody has yet convinced physicists that their place has been usurped by biotechnologists. But my naïveté was also symptomatic of an attitude still endemic among natural scientists generally—after all, why wouldn't those who study the nuts and bolts of creation be well-equipped to judge the merits of other academic disciplines?
That attitude seems to largely explain Richard Lewontin's notion that scientists have a special claim to “political rationality”. Last week I found this assertion sorely wanting. In this (two-part) post I will illustrate by example the maxim that
The further you venture from your academic specialty, the greater a moron you become.
As in last week's offering, Exhibit A will be Douglas Futuyma.
But first a disclaimer. Professor Futuyma is, by all accounts, a distinguished biologist. At least one member of my dissertation committee knows him both professionally and socially. Nothing in what I write below ought be taken as a personal attack. Nonetheless: When one undertakes to educate the public on a given topic, it is highly advisable to put forth enough effort to get basic facts correct.
In 1983 Futuyma published Science on Trial: The Case for Evolution. A second edition—which I will quote from here—appeared in 1995. In additon to being a robust defense of evolutionary biology, Science on Trial also attacked the movement known as Scientific Creationism—effectively, if sometimes shrilly. But Futuyma is out of his depth whenever he ventures away from the biology.
[Aside: Scientific Creationism attempts to demonstrate (1) that the creation of life occurred in the recent geologic past—roughly 6000 to 12000 years ago; (2) that many geological features can be explained by the effects of Noah's Flood; and (3) that evolution—if it occurs at all—only takes place within strictly defined limits. The doctrine attempts to borrow the trappings of science, but in the end has as much claim to scientific validity as your average episode of Star Trek: Voyager.
Theologically, this form of creationism is based upon what is sometimes called a “folk exegesis” of Genesis. If such literalist interpretation is your favored form, I will not quarrel with you. But if that is the case, kindly keep it within the realm of faith: it is not science, and I am not interested in answering any attempted “scientific” defenses of young-earth creationism.]
An early sign of trouble is found in Chapter Four, “The Fossil Record” (emphasis added).
The very same processes of atomic change that result in radioactive decay are those that enable us to build atomic weapons and nuclear reactors. The physics of these processes is very well understood—perhaps too well. Physicists have found that these processes are responsible for the “evolution” of the elements that occurred when the “big bang” formed the universe about fourteen billion years ago. The fusion of hydrogen atoms into helium atoms, which is occurring right now inside the sun, is the same kind of process that gave rise to all the rest of the elements during the big bang. (p. 71)
There is a double error here. First, Futuyma is conflating radioactive decay (in which unstable isotopes of certain elements emit subatomic particles and/or photons) with nuclear fusion (which, as the name implies, is the fusing together of atomic nuclei, with some of the rest mass of the constituent particles converted to energy). This would be like mistaking apples for oranges, if only crabapples could smash together to form unblemished Granny Smiths, and grapefruits could give birth to tangelos (thereby becoming mandarins in the process).
Second, the full panoply of elements was not spawned in the Big Bang. During the first three minutes after the fireball, isotopes of the very light elements—primarily hydrogen, with vanishingly small fractions of helium and lithium—were indeed formed. But a half billion years would pass before nucleosynthesis within the first stars could begin. What's more, stellar fusion cannot create nuclei any heavier than iron—so that the heavy elements did not exist until the first massive stars blew themselves apart as supernovae, nearly a billion years after the Bang.
This is not arcane knowledge: Futuyma might have found it all by perusing a sophomore physics text, with perhaps a general astronomy reference thrown in for good measure. But he didn't, and hence a chapter intended as an epitome of the True Scientific Story of Life, the Earth, and the Universe runs aground on its third page.
But that's nothing: just wait until he tries his hand at history. Stay tuned for part II.
In response to Lewontin's preposterous assertion about the necessity to understand quantum mechanics and molecular biology to be qualified to vote, I would sooner trust the vote of a person who knows how to operate a MIG welder and a skiploader.
My father is a physicist. He used to (I think jokingly) claim that not only could physicists do anything anyone else could do but that they could do it better than they could.
Yup. Sounds like a physicist.
It's no wonder that social constructivism has such appeal for social scientists and humanities types. I mean, they're wrong...but still no wonder.
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