Scott Alexander and others on mental illness

Here is Scott’s response to Bryan Caplan’s response to Scott’s critique of Bryan’s earlier Szaszian paper on mental illness.  I can’t bring myself to do any serious recap, so I hope you care (or do I hope you don’t care?), in any case Scott serves up the links:

In 2006, Bryan Caplan wrote a critique of psychiatry. In 2015, I responded. Now it’s 2020, and Bryan has a counterargument.

Bryan rejects the concept of mental illness, believing that such individuals can be described using concepts from rational choice theory, most of all preferences and meta-preferences:

…this article argues that most mental illnesses are best modeled as extreme preferences, not constraining diseases.

Most lately, here is a snippet from Scott’s latest post:

Or what about respiratory tract infections that cause coughing? My impression is that, put a gun to my head, and I could keep myself from coughing, even when I really really felt like it. Coughing is a preference, not a constraint, and Bryan, to be consistent, would have to think of respiratory infections as just a preference for coughing…

Bryan’s preference vs. constraint model doesn’t just invalidate mental illness. It invalidates many (maybe most) physical illnesses! Even the ones it doesn’t invalidate may only get saved by some triviality we don’t care about – like how maybe you can lift less weight when you have the flu – and not by the symptoms that actually bother us.

I am fully on Scott’s side here, but I think he is being too literal in responding to Bryan’s arguments, taking on too much of Bryan’s turf.

The biggest problem with Bryan’s argument is this: let’s say you could redescribe say schizophrenia in terms of an unusual preference and other concepts from rational choice theory.  It would not follow that is all schizophrenia is.  For instance, a quick perusal of the literature shows that schizophrenic individuals may suffer from local processing deficits (moving too rapidly and too indiscriminately to global processing), working memory defects, inability to maintain attention, disorganized behavior, hypo- and hyper-excitability, excessive speculative ideation, excess receptivity to information from the right hemisphere of the brain, and delusions.

Of course that account is contested at some margins, as is typically the case in a research literature, but you get the point.  Schizophrenia could be some combination of an extreme preference, whatever else Bryan wishes to toss in, and some version of that list from the paragraph directly above.  Bryan works very hard to “rule in” his redescription of various mental illnesses, but he doesn’t and indeed cannot do much to rule out what are in fact the relevant cognitive or sometimes personality traits of the phenomenon in question.

And if you ask “Ah, what about the ‘normal’ people who claim that God is talking to them?”, well most of them have only a limited number of the features on that above list.  Some of course may in fact be schizophrenic or fall into the broader schizotypic category.  Those supposed reductios about the supposedly wacky religious people just don’t much dent the category of schizophrenia.  There might even be a correlation in the data between religious behavior and schizotypy — why not? — but the two are by no means cognitively identical.

Ask Bryan a simple question: do the individuals diagnosed as schizophrenia in fact have some combination of those traits listed above to an unusual degree?  If he answers “yes,” he has in fact conceded the argument.  If he answers “no,” he needs to counter a huge and established literature with empirics of his own, which of course he has not done.  The broader point is you cannot usually vanquish empirical categories with philosophical and methodological arguments alone.

I do partially side with Bryan only in one regard: I don’t find the term “mental illness” very useful, and very often it is misleading, or even dangerous, or used to restrict the liberties of individuals unjustly.  I very much prefer a more disaggregated approach, citing more exact information about a person’s condition, rather than applying a very general label in a manner that could end up being irresponsible.  It seems to me that a more disaggregated description is almost always possible, maybe always possible.

But you shouldn’t take that brand of skepticism as endorsing the kind of mono-conceptual straitjacket Bryan wishes to impose on this whole problem.