Functional Irrationality (1)
The view that some forms of irrationality may serve a useful purpose is being increasingly entertained, despite the disquiet it elicits. The reason for the disquiet isn't difficult to discern, for if the view were made good it might threaten the unqualified normative primacy that rationality enjoys in the evaluation of thoughts, beliefs, intentions, decisions and actions. In terms of the predominant "rational explanation" model, reasons both generate and justify actions, and carrying out the dictates of reason is held up as an ideal. If it can be shown that under some circumstances or for certain types of action irrational elements or procedures would produce "all things considered" better results, this would put these deliberative "ideals" in question.
Nozick (1993), going deeper, advances the view that we accord rationality intrinsic value (over and above its instrumental value), because deciding and believing in a way that is responsive to "the net balance of reasons" has come to form an important part of human identity.
We value a person's believing and deciding rationally in a way that is responsive to the net balance of reasons, and we think that is good and admirable in itself, perhaps because so deciding and believing uses our high and intricate capacities and expresses them, or perhaps because that embodies an admirable and principled integrity in guiding beliefs and actions by reasons, not by the whims or desires of the moment. (Nozick 1993: 136)
In this paper I want to explore whether such entrenched assumptions and intuitions preempt a coherent account of functional irrationality, or whether, despite the presumption against it, it can be defended within the purview of traditional conceptions of rationality and reason.
II. On the very possibility of irrationality
The claim that beneficial results are to be had from irrationality is up against difficult odds, (2) which are aggravated by a longstanding tradition opposed to the mere possibility of irrationality — one which alleges that even the attempt to describe the supposed examples engenders paradoxes which can be dissolved only if redescriptions foregoing assumptions of irrationality are provided.
This scepticism about irrationality derives much of its initial plausibility from a central assumption of the traditional conception of rationality, viz., that consistency in and between an agent's beliefs, desires, intentions, judgements, and so on is a necessary condition for the intelligibility of her conduct or behaviour. (3)
But of late, this assumption is coming into question (4) and relations between these elements other than the purely "rational" are sometimes admitted as significant. (5) In addition, the view of these mental elements as homogeneous atoms has been challenged by analyses which ascribe to them complex internal structures and (corresponding) genetic histories. (6)
So it seems that the way...