Monday 16 December 2013

Schizophrenia & the nature of delusions: to believe or not to believe?, Ecole Normale Supérieure de Lyon

I am at a two day workshop on delusions in Lyon organised by Jean-Michael Roy (pictured) and with a focus on the doxastic versus non-doxastic distinction to which he has clearly given some considerable thought. One question raised by the relation of his conception of the general framework to individual papers by others is not so much whether the distinction can be applied but whether it is the best or most helpful distinction. I'd be interested to know, however, what might replace it if it isn't.

After a very thorough taxonomy of possible positions offered by Jean-Michel, Sean Gallagher seemed surprised and faintly disturbed to be classed as occupying a kind of doxastic position. He suggested the analogy of taking a bath: in so doing, beliefs are involved but that isn't what having a bath is mainly about. So whilst his account has implications about beliefs, he wanted to resist the doxastic label. 

In his presentation, he recapitulated the account given in his paper in the Broome and Bortolotti 2009 book which criticises both top down and bottom up accounts and sketches a more general idea of delusions as the inhabiting of a different and delusional world. This, he suggested, allowed for the description of all the standard ways in which delusions have surprising properties. But he went on, beyond that paper, to present a kind of two factor biological account, plus cultural factors to shape specific content. (The second factor being a pair of localised brain mechanisms for failing to spot cognitive errors to distinguish between healthy occasional suspension of reality whilst reading novels etc. and a more permanent delusional suspension.)

I was a little unsure about how the two themes fitted together. I guess the former picture is non-doxastic in the sense that Sean's preferred  account of access to the real world is not based on intellectual, theory-theory theorised beliefs but on a richer embodied orientation. So, to put it flippantly, he also has a non-doxastic account of beliefs. But I wasn't sure what the idea of different world really added to any agglomeration of piecemeal descriptions of delusions provided by their subjects or by clinicians. And then I wasn't sure how it related to the two (plus one) model of delusions which followed. Perhaps these are simply two independent ventures: an analysis of the nature of delusion and a suggestion for their causal explanation.

Joining us on Skype, Keith Frankish presented a thumbnail sketch of his account of delusions as acceptances. Starting with a distinction between type 1 and the 2 beliefs as:
1: behavioural dispositions which are non-conscious, accessed either by actual behaviour or sometimes by imagining what one would do and strongly subject to rational norms
2: occurrent thought which are conscious, available to verbal report, weakly subject to rational norms (slips of mind etc). (They are also controlled, discrete, binary.)

Compared to these two options, delusions look more like type 2 beliefs. But they, generally, look even more like acceptances, he argued. An acceptance is the strategy (cf of scientists or lawyers) of using propositions as premises of hypotheses but with no need actually to believe them. This picture assumes reasoning is intentional, consciously controlled and binary (like type 2 beliefs). But it can be pragmatically motivated (unlike type 2 beliefs). And it can be context relative (again unlike type 2 beliefs).
On this model, type 2 belief is thus a subset of acceptances: unrestricted, evidence-sensitive acceptance or 'doxastic acceptance'.

So the claim that delusions are acceptances amounts to either:
Option 1 doxastic acceptances.
Option 2 non-doxastic acceptances.
If option 1, then they are improperly executed doxastic acceptances ie. irrational beliefs. If 2, they were never intended to be unrestricted: rational pragmatic acceptances. As indirect evidence for this idea, Keith suggested that this picture coped well with Akrasia. 
1: the action dictated by a promising policy is incompatible with some other desirable action and
2: the desire to perform this other action outweighs the desire to carry through one's premising policy.
Similarly for delusions not motivating action. And hence this suggests new questions about, not what causes someone to believe that they are dead, but what purpose does the adoption of such an acceptance for the purposes of argument serve?

I asked whether he worried about whether subjects with delusions conceived of them as acceptances. He replied that the policies which fixed an acceptance were type 1 beliefs and desires and hence non-conscious and hence subjects did not so conceive their delusion. It slowly dawned on me that this seems to suggest something like this picture. Conscious type 2 states are the result of non-conscious type 1 states which - interestingly - are nevertheless second order (not his terminology) in so far as they are about policies for dealing with contents (so beliefs about beliefs etc). So the conscious access to type 2 seems to come out if nowhere. One discovers the nature of one's type 2 state (does this include the difference between beliefs and desires as well as doxastic and non-doxastic acceptances?) by interpreting oneself (as others do). This was a price he was prepared to pay. (Standard hermeneutic worries that I may have got hold of the wrong end of the stick apply more than usually to this account of his views, I should add.)

Just now I am listening to a talk by Patrice Soom offering a formal model based on functionalism of the claim that delusions might impact on other mental properties but not vice versa. One claimed virtue is its immunity to objections to the DSM definition such as a commitment to doxastic statement, the extrinsic characterisation. It fits the Coltheart etc two factor model. It is a brave account that any unrevisable belief is a delusion but Patrice was hip to this and embraced it is an interesting prediction of the model. Still, I can't help thinking that a question has been begged in ascribing contents - eg. that they are dead - and then adding to that the subject does odd things with that content (in this case, regards it as unrevisable). I can't help being suspicious about ever using the sentence: 'Jones thinks that she is dead'.

PS: Keith has now (18/12) sent me a substantial email correcting my understanding of his view. Once I've digested it, I will post a follow-up.

Friday 13 December 2013