June 7, 2009 11 Comments
BoingBoing posted one of Robert Sapolsky’s (Stanford neurobiologist and author of Monkeyluv, The Trouble with Testosterone and Why Zebras Don’t Get Ulcers) lectures on schizophrenia and schizotypal personality disorder today. It’s an hour long, but makes for pretty interesting listening if you have the time to give it. In this installment he starts off speculating about the possible selective evolutionary advantages of schizophrenia, which—unlike cystic fibrosis and sickle-cell anemia, which protect heterozygotes (carriers, usually with one good copy of the gene) from cholera and malaria, respectively—hasn’t been thought to confer any kind of selective advantage.
He suggests an advantage exists, and that it lies in schizotypal personality disorder—sufferers who display milder schizophrenic symptoms and are labeled “half-crazy.” A group of scientists studying adoptive and biological schizophrenics in Denmark discovered, after interviewing all the parties concerned over a period of (I think ten years) that many relatives of schizophrenics display this attenuated version of the disease, which he characterizes as “movie-projector syndrome.” These people tend toward the antisocial; they prefer isolated occupations and are guilty of “metamagical thinking,” a near-schizophrenic kind of mental process that protects the sufferer from ostracism by successfully channeling odd or schizophrenic qualities into their proper contexts.
I haven’t tracked down his lecture on schizophrenia itself yet and I’d like to, because that definition of schizotypal personality disorder is rhetorically a bit too pat and makes it easy for him to (for example) retroactively ascribe it to shamans, witch doctors, medicine-men and religious founders generally. Anyone who thought he heard a burning bush talk or believed he was talking to a man who’d risen from the dead (or indeed claimed to have risen from the dead himself) would, today, be diagnosed with schizotypal personality disorder.
This is clever, of course, but it’s the argumentation I’m objecting to. I realize this is just a lecture, but it’s disappointingly poor logic from a defender of rationalism. To suggest that a newly developed (and rather hazy) diagnosis, rooted in a spectrum of sane vs. insane behaviors and defined only by a list of symptoms that have a priori been categorized as “schizotypal” or “insane,” can be applied to someone thousands of years ago who has precisely those milder “insane” symptoms is a textbook example of petitio principii, begging the question. I have developed this definition, it says, and look! someone a thousand years ago fits it!
(The difficulty lies, I think, in locating the definitional limits of schizotypal metamagical thinking. Is there any irrational or metamagical belief that wouldn’t be automatically classified as schizoid/schizotypal? Is it a matter of cumulative weight? Sapolsky mentions that 50% of Americans believe in UFOs, but wouldn’t (I assume) classify half the population as half-crazy. Is it then a matter of authorship—it’s one thing to hold an irrational belief that’s been culturally transmitted, another to create an entirely new one of your own? I think he’s getting at the latter, and suggesting that your evolutionary “fitness” depends on your ability to persuade other, more rational creatures of the truth of your idiosyncratic vision.)
Having established (which he hasn’t, at least not in this lecture) that important religious figures in different societies were schizotypal, he uses this to prove that in fact people who suffer from schizotypal personality disorder actually wield a hefty amount of power and had no trouble reproducing and passing on their genes. No data is cited to support this, and he dismisses the fact that many religious figures (both in shamanistic cultures and mainstream religions) were proscribed from marrying and asserts that indeed schizotypal personalities (unlike their schizophrenic counterparts) were and are reproductively quite successful.
I’m skeptical about both retrospective claims for a couple of reasons. One, I’d be interested to see hard statistics on the reproductive success of major religious founders. It seems to me that anecdotally, at least, they fall into two extremes: celibacy or some version of cult-leader polygamy. Two, the line he draws between schizotypal and schizophrenic is the second case where he uses the conclusion to prove the premise. His argument goes thusly:
- Schizophrenic people are not reproductively successful and can’t behave appropriately according to context.
- Schizophrenics are therefore ostracized from society.
- People with schizotypal personality disorder are milder cases that can channel their putative schizophrenic experience properly (for example, they’ll have an epiphany in church, not on a street corner).
- Schizotypals are not ostracized from society.
- Therefore, because religious founders who claimed to converse with bushes, etc., were not totally ostracized from society, they must be schizotypal personalities.
This is logical and historical nonsense. Read more of this post