Thursday, 4 June 2020

On not being very interested in natural kinds in psychiatry

I’m writing one of these new short format (25-30,000 words) mini-books on mental illness. Having plotted the first 60%, I’m struggling to work out how to approach the final 40%, an outline of which I submitted as part of the proposal.

I took some time out to write a paper on dementia and narrative identity (which seems to have gone ok), a 5,000 word entry on tacit knowledge for an edited book on implicit knowledge (the editor didn’t like the line I took in the first version so I’ve drafted a second) and a misguided chapter on the saying-showing distinction in the later Wittgenstein (I sent the editor a 4 paragraph outline, warning that I couldn’t write what he really wanted – on the saying-showing distinction in the early Wittgenstein - but could offer this; he accepted the outline as ‘fitting the concept’ of the book but when, only 10 days later, I submitted the chapter, he rejected it in a single sentence email as not ‘fitting the concept’; oh well). But I ought to be back to the mental illness booklet.

It has taken me a few days to understand my resistance to returning to the CUP mini-book. I now realise that it is is an emotional response.

When I think like a university lecturer about what should be included for the sake of the reader/student, I think it should include some discussion of the kind of kinds that might properly belong to psychiatric taxonomy. There has been much discussion of this from both psychiatrists thinking of the revisions of the DSM and philosophers. Abstract models have been put forward. Perhaps the most influential one right now is a renamed version of Boyd’s homeostatic property clusters: mechanistic property clusters. Such a model relaxes any essentialist assumptions on kinds. There are also related issues such as whether we should look at a level lower than whole syndromes / DSM diagnoses as RDoC suggests and to cross level causal factors.

But the fact that there may be cross level causal factors (and perhaps therefore no such thing as levels) that constitute kinds of some sort via such clusters isn’t why I got into philosophy. And yet that is seen as the most legitimate of philosophy of psychiatry activities. I’m not really interested but I don’t have a ready way to show that I have any right not to be interested. What would be such a right?

Here’s a thought: showing that it at least might be missing the point. We know that the RDoC isn’t really interested in dysfunction but function and causal explanations across many putative levels of ‘symptoms’ rather than syndromes. (I scare quote because the interest in function rather than dysfunction counts against the word ‘symptom’.) So it isn’t going to help with the very idea of mental pathology. Nor does a relaxed model of kinds help with the status of DSM diagnoses. There might be homeostatic / mechanistic property clusters underpinning aspects of ADHD but there might be for same sex sexual attraction or for political dissent in the USSR. That there might be H/MPCs solves a different problem to the one that strikes me as worth philosophising about. My interest does not lie in whether there might be mixed bottom up and top down explanations of some aspects of human experience so much as why we want to categorise conditions as mental illnesses. It’s that top down question rather than causal explanations of how such conditions, once we’ve identified them, are sustained that seems the proper object of philosophical inquiry. But I feel distinctly old fashioned in not finding the possibility of relaxed natural kinds really interesting in itself.