Thursday, 6 December 2007

Rationality and Compulsion #2

In the end, I was a little disappointed with Lennart Nordenfelt’s book Rationality and Compulsion (mentioned before). The second half ‘Irrationality, compulsion, and mental disorder’ applies the framework of ‘action theory’ from the first half to consider mental disorders. My qualm is two-fold.

Firstly, the real business of the book is postponed to the final two (of nine) chapters which does not seem to be enough of a return on the investment of coming to grips with the theoretical framework.

Secondly, I’m not sure that the framework really pulls its weight. Recall that the book is called Rationality and Compulsion. The final chapters discuss compulsion explicitly. Nordenfelt takes a condition of adequacy of any analysis of compulsion that it reflects the fact that if someone is compelled to do something then they could not avoid doing it [141]. Thus the analysis of obsession is a good opportunity to see what the action-theory framework can do. He considers the example of a subject who obsessively checks that she has turned off a tap.

The subject believes… that a risk exists that the water is still running from the tap. At other moments… she believes that this cannot possibly be so. Subjectively, overwhelming evidence also exists that the taps have been turned off. The situation can perhaps be described as follows: the subject cannot help having a completely unjustified, indeed foolish, belief...
[I]t is primarily the belief that the tap is running that is compelling. [177]

But there is no explanation of the tension in this case, the point that the subject believes both that the tap may be running and that it cannot be. Elsewhere, in the case involving wants as well as beliefs, Nordenfelt suggests that there are ‘conceptual’ limits to irrationality or a lack of fit between mental states and actions.

If a person genuinely wants to do F, has no conflicting want to do non-F, believes that he or she can do F, is capable of and not impeded from doing F, then he or she must for conceptual reasons at least try to do F. If A does not attempt to F, then something must be wrong with the premises. [117]

And earlier he expresses doubts about the psychological possibility of entertaining incoherent or conflicting beliefs.

A person who believes that both p and non-p at the same time has an incoherent belief. A logician would say that such a belief is irrational and logically forbidden. An interesting problem is whether such a belief is even psychologically possible. [100-1]

He goes on to argue that it is psychologically impossible to entertain a belief in the incoherent conjunction but that it is possible to hold a conjunction of beliefs which turn out, on investigation, to be incoherent. But this will not apply to the obsessional case (it is not a matter of investigation that the tap cannot be both on and off). Thus the account of the obsessional case does not seem to advance our understanding of it at all. Subjects of obsessional thoughts are compelled to have conflicting beliefs but we are not told anything about the nature of that compulsion.

Perhaps the best possibility for developing an account of obsession from the materials found in the book comes from its separation of rational and causal factors.

If no contact (or no relation whatsoever) exists between a particular want or set of beliefs, on the one hand, and an action on the other hand, it is not sensible to talk about the former being defective reasons for the latter. In order for a defective reason for F to occur, some relation must exist between the reason and the performance of F. And consider again the two plausible relations in this context, namely a causal relation and a rational relation. [114]

He goes on to suggest that a causal relation can exist even when the wants and beliefs ‘defectively rationalise’ the action. Further there is much talk of reasons being 'strong' or 'idle' which seems to mean causally strong or weak. But since he argues that ‘[r]ationalisation is a relation totally different from causation’ [97] this raises the question, which is simply not touched on, of what connection there is between rationalising force and causal force. Nordenfelt simply assumes a harmony between these two factors in most cases without saying why the ‘conceptual reasons’ that obligate action in the case quoted above also cause it. But this is surely the key question for a book that examines the relation of rationality and compulsion.