Friday, January 23, 2009

How Science Works

I've read the same illegitimate argument twice in the last week, so it's probably worth bolgging about it, exposing its problems. The conclusion that we are to draw at the end of this argument is, "Rest assured, if evolution were wrong, so many scientists wouldn't hold to it." (I blogged about a similar, but slightly different, argument a few weeks ago in this post.) The following passage comes from the bestseller The Language of God, by Francis S. Collins, who was the head of the Human Genome Project.
One of the most cherished hopes of a scientist is to make an observation that shakes up a field of research. Scientists have a streak of closeted anarchism, hoping that someday they will turn up some unexpected fact that will force a disruption of the framework of the day. That's what Nobel Prizes are given for. In that regard, any assumption that a conspiracy could exist among scientists to keep a widely current theory alive when it actually contains serious flaws is completely antithetical to the restless mind-set of the profession.
The main problem with this line of reasoning is simply that it's not true. That's not the way science works. But let me pause here to make a point, one that comes up over and over again. Collins is here pontificating on an area outside of his training and expertise (which is why his reasoning goes so far astray). Collins is a biochemist, geneticist, and medical doctor. The issues involved in his claim here--the process of discovery and how scientists behave--are the subjects not of biochemistry and genetics but of philosophy of science, history of science, and sociology of science. And the experts in these fields would sharply disagree with the fairy-tale scenario at the heart of Collins' argument.

The essential book on this topic is by Thomas Kuhn, and is titled The Structure of Scientific Revolutions. His theses are well-regarded among historians and philosophers of science, and his book is considered one of the 100 most influential books of the 20th century. And apropos to Collins' claim, Kuhn's main theses are these... That most of scientific endeavor is what he terms normal science, which is merely the further extension of an existing paradigm (such as Newtonian physics or neo-Darwinian evolution), and that paradigm shifts (or scientific revolutions) occur only with a great deal of hesitation and angst among a community of scientists most of whom can never accept a different paradigm than the one in which they were raised. In other words, the overwhelming majority of scientific research is done in an effort to bolster a currently-held view, no matter how wrong later scientists will come to consider it.

In direct contradiction to what Collins claims, Kuhn writes the following (and where Kuhn mentions 'paradigm,' think of neo-Darwinian evolution, which is the paradigm in biology today),
Mopping-up operations are what engage most scientists throughout their careers. They constitute what I am here calling normal science. Closely examined, whether historically or in the contemporary laboratory, that enterprise seems an attempt to force nature into the preformed and relatively inflexible box that the paradigm supplies. No part of the aim of normal science is to call forth new sorts of phenomena [say, irreducible complexity]; indeed those that will not fit the box are often not seen at all. Nor do scientists normally aim to invent new theories, and they are often intolerant of those invented by others. Instead, normal-scientific research is directed to the articulation of those phenomena and theories that the paradigm already supplies.
Kuhn would probably have answered Collins that one need not appeal to 'conspiracy' to challenge neo-Darwinism. Rather, the paradigm of neo-Darwinism was so fundamentally a part of the education and training of today's biologists, that they cannot even see or think clearly about any evidence that would call that paradigm into question. Kuhn avoids using the word 'indoctrination,' but his descriptions of the normal training of scientists makes it clear that the result is the same.
The study of paradigms [again, think 'evolution']... is what mainly prepares the student for membership in the particular scientific community [biology] with which he will later practice. Because he there joins men who learned the bases of their field from the same concrete models, his subsequent practice will seldom evoke overt disagreement over fundamentals. Men whose research is based on shared paradigms are committed to the same rules and standards for scientific practice. That commitment and the apparent consensus it produces are prerequisites for normal science, i.e., for the genesis and continuation of a particular research tradition.
Collins might be excused for his general lack of understanding of these things, since he is not a philosopher or historian of science. (Though, by the same token, he ought to be admonished for making such confident claims in fields in which he betrays himself as grossly undereducated.) But glaring counterexamples should cause him to question his claim, and only a few pages later he discusses one such example (without, apparently, recognizing that it refutes his earlier statement).

Einstein's famous equations clearly led to the revolutionary notion that the universe is expanding and that it had a beginning. But this conclusion was at odds with the paradigm of his day, which held that the universe is eternal and static. Far from recognizing this as his chance for greatness as an innovator, Einstein succumbed to the herd mentality and introduced (without any other justification) a fudge factor into his equations that neatly avoided these clear conclusions. Even Einstein could not trust his own reasoning and equations, but made them subservient to the 'inflexible box,' the scientific (and metaphysical) paradigm he had been taught.

The bottom line is that consensus among biologists is a bad argument for the truth of neo-Darwinism. It is fallacious (it's an example of the ad populum fallacy); and Collins' version of it is dead wrong. Questioning the paradigm that one has been taught is extremely difficult for scientists. To the biologist today, "evolution is fact" is merely a way of saying that all they have ever been taught leads them to see the world through evolutionary lenses, and that they are simply unable to recognize--much less deal seriously with--evidence that would call that paradigm into question.

1 comment:

Av8torbob said...

You nailed that one, Rick. What a great summary of the issue. I really appreciate the way you frame your arguments.

Speaking of Collins ... I hope you find the time/motivation to discuss his (and Behe and ...) adherence to common descent. It is a sticky subject for me and I would love to hear your detailed take on it beyond the email stream at RTB. I greatly respect your opinion and would love to be able to follow through on the arguments you make in that regard.

Oh, and congrats on the big soccer win!