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Philosophy of Mind

Functional Irrationality (1)

Mary Tjiattas
University of the Witwatersrand

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ABSTRACT: 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 is not 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 actions irrational elements or procedures would produce ‘all things considered’ better results, this would put these deliberative ‘ideals’ in question.

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I. Introduction

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 has been paved for analyses of irrationality in terms of which the lack of fit between, e.g., beliefs, desires, judgements, intentions and actions is responsible for the varieties of irrationality, including akrasia and self-deception (the former manifesting a breakdown between evaluative judgement and ensuing action, the latter a breakdown between evidence and belief).

Amélie Rorty's work, for example creates a space for such studies by challenging the assumptions which cast doubt on the existence of genuine irrationality. This space accommodates not only "apparently anomalous psychological activities" (Rorty 1988: 195), but also the resources and mechanisms that contribute centrally to psychological well-being and which form part of necessary conditions for proper functioning, e.g., self-transformation. (8)

It may however be questioned whether in the end such accounts accommodate genuine irrationality. Such phenomena as sticking to principles, which could seem irrational when viewed in isolation, can be construed as a device which works in the service of an ultimately rational end if the net is cast sufficiently widely. This might require an increase in the range of beliefs, desires, etc. included in the account, and a recognition of relations between beliefs other than evidential support or fit. However, a suitably rich notion of rationality ought to be able to accommodate a wider variety of such psychological relations.

But this invites the response that a situation which includes irrationality that can be thus accommodated still turns out to be less rational than one which involves no irrationality at all. To make a case for functional irrationality it must be possible to find tolerable the idea that, as Nozick puts it,

... a total package of such apparently irrational tendencies [could] even work better together than the total package of apparently — when separately considered — rational tendencies (25), (9)

and this, it seems would require that we defeat Davidson's (1985: 148) claim that

Nothing can be viewed as a good reason for failing to reason according to one's best standards of rationality.

Nozick insists on the possibility that our expectations of rational connections between beliefs and evidence, decisions and action and so on may fail in such a way as to result ("paradoxically") in more effective action or more desirable consequences than rationality could have secured. (10) Taking sunk costs and symbolic values into account, adhering to principles, although violating standard decision theory may result in richer, more rewarding lives (through promoting integration both contemporaneous and temporal).

Annette Baier's discussions of trust also raise telling questions about the rationality of going along with "unjustified" attitudes. In answer to the question "Why would rational persons make themselves vulnerably dependent on others?", it is clear that from the perspective of rationality the answer must be that there is no good reason.

Nonetheless the "...innate readiness of infants to initially impute goodwill to the powerful persons on whom they depend" (Baier 1994/5: 107) is a precondition for survival and for the possibility of later, more conscious, forms of trust. Lest it be suggested that this is a situation applying only to our immature condition, Baier (1994/5: 172-3) points out that even the agreements of the contract situation rely implicitly on a more primitive assumption of trusting.

Unless one trusts one's fellow discussants to be engaged, as she purports to be, in the same enterprise as oneself ...then the whole justificatory discourse becomes a farce, or a contest of wills.... Until we can trust those with whom we are talking...no justificatory discourse can be sustained, no principles get ratified or vetoed....Some more basic sort of fidelity must already be implicitly recognized and exhibited in our speech behaviour if our putative acceptances and rejections of principles are to carry any force. If they do not, then nothing that we say about our acceptance or rejection of proposed principles will be worth the wind it is written on.

Why call such trusting irrational in spite of its desirable consequences? Because those consequences, desirable as they might be, could not be a good reason for that trust.

III. Explaining the functionality of (some forms of) irrationality

Given the assumption that there are clear cases of functional irrationality, how is this to be explained? An answer to this seems to be suggested by some of the attempts to account for the existence of irrationality as such. Some forms of irrationality are causally necessary conditions of possibility of rationality, developmental, temporal or otherwise. While not themselves meeting criteria for rational thought and action, they make it possible for their conditions to be established.

The approach to rationality that emphasises the "irrational" means employed in achieving it results in a conception of rationality that is more differentiated and complex than the traditional one, and which is more able to cope with the phenomena. Accounts of non-rational psychological mechanisms and strategies allow for a view of rationality as something gradually and indirectly attained, for otherwise inexplicable or problematic mental phenomena as pre-rational stages or constituents or conditions of rational end-states. Rorty (1988: 262) makes an eloquent case for an enriched conception of rationality:

Even when a person takes rationality to be more than a crucial criterion for the legitimation of his various ends, even when he takes the exercise of rationality to be the end with which he primarily identifies himself, it cannot provide the sole or sufficient principle of choice. It cannot by itself provide the range of aims and directions required for a recognizably human life....the standard story of rational agency requires strong modification. Not only are human agents more complex and conflicted than the naive accounts of rational agency project, but the various functions of rationality in agency are themselves often in latent conflict. The psychological strategies exercised in self-deception and akrasia operate quite independently of rationality. That, indeed, is precisely their contribution to rational action: a rational agent could not do without them. Such an agent would have no focus for attention: his psychological field would be nonperspectival, without preference. He would be a rational agent, without any reason to act this way rather than that.

Must we nevertheless insist on asking whether the conceptual space for such a conception (and its attendant motivational aetiology) would be acquired at the expense of privileged connections between evaluative judgement and intentional action? Davidson's (1982: 303) expressed the problem thus:

The underlying paradox of irrationality, from which no theory can entirely escape, is this: if we explain it too well, we turn it into a concealed form of rationality; while if we assign incoherence too glibly, we merely compromise our ability to diagnose irrationality by withdrawing the background rationality needed to justify any diagnosis at all.

The trick is not to explain the phenomena so well that one loses them.

So perhaps invoking functionalist explanations, does too much too soon. For it allows the assumption that there are limits to reason (perhaps even constitutive ones) that leave room for understandable, intelligible, even justifiable irrationality.

What pull should we allow the traditional conception to exert? That its influence is considerable is obvious: we find it very difficult to allow that forming a belief in the face of counter-evidence could be preferable to desisting from doing so, or to imagine circumstances in which this would be epistemically warranted. (11) Furthermore, we are hard pressed to find grounds on which to commit ourselves unequivocally to a general policy of supporting less than fully rational procedures. (12)

Rationality exerts great normative force. Even psychoanalysis, the discipline most dedicated to the exploration of irrational phenomena attests to this. For a central goal of clinical work in psychoanalysis is to bring the analys and to the point where she can recognise and acknowledge the underlying rationality of her irrationalities. But in scrutinising this reluctance to admit irrationality we need to recognise that it may well be rooted in deep but unjustified assumptions about human nature. As Jon Elster (1989) insists, the belief in the omnipotence of reason, the expectation that it will yield unique prescriptions and predictions, is just another form of irrationality. Rationality itself requires us to recognise the limitation of our rational powers (Elster 1989: 17),

As in Kant's critique, the first task of reason is to recognize its own limitations and draw the boundaries within which it can operate

and such circumscription could well have the effect of legitimating some forms of irrationality.

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(1) Although the term "functional irrationality" is my own, it is suggested by Amélie Rorty's distinction between the functionality and the rationality of psychological attitudes. In a number of different ways, and with respect to different such attitudes, she considers what attitudes it is reasonable to take towards irrational but nevertheless functional psychological states (ones that increase our "functional resourcefulness").

(2) Appeal to the beneficial nature of the results is crucial for my purposes, for showing merely that something has a function is insufficient warrant for promoting it. Functional justification needs to include a convincing argument for the desirability of the function.

(3) For Davidson, the "basic methodology of interpretation" says that inconsistency breeds unintelligibility. "What sets a limit to the amount of irrationality we can make psychological sense of is a purely conceptual or theoretical matter — the fact that mental states and events are constituted the states and events they are by their location in a logical space." (Davidson 1982: 303)

(4) See e.g. Bratman's (1987) work on intention.

(5) Some nice examples from Rorty (1988: 11) concern such psychological facts as desires and attitudes affecting perception or interpretation — when trust is lost, a previously benign face looks shifty; a desire to see a Rembrandt affects an interpretation of a passage in Spinoza. Similarly, memories often affect and individuate current desires and emotions.

(6) Much of the latitude allowed to investigations of irrationality may be attributable to the general dissemination and acceptance of models of psychic functioning that strive to represent the complexity of human motivation, and the implications for interaction with other aspects of mental functioning. Amélie Rorty (1988: 13) argues that "Most psychological and cognitive activities are multilayered and multifunctional, playing a number of distinctive roles simultaneously". Work such as Johnston's (1995) on subintentional processes and Dunn's (1995) on mental tropisms, pursues the idea that rational mental functioning is an outgrowth of less developed "irrational" processes and procedures, and so never quite attains complete autonomy. Dunn refers to "helpful mental tropism", a purposive subintentional process whereby anxious desire creates and maintains such psychological conditions as conduce to self-deceiver's enjoying his belief (Dunn 1995: 330). Johnston's sub-intentional processes are purposive but not intentional, involving simple (blind) regularities where causes need not be reasons. As a pervasive part of the mental, they underlie everyday mental inferences, but they are also involved in non-accidental purpose-serving mental regularities, e.g. self-deception and more complex Freudian processes like repression.

(7) This is, of course, an oversimplification. See e.g. Rorty (1980) for an account that is nuanced and complex.

(8) A number of such functions are systematically discussed by Davidson (1982). He explores the possibility that irrationality and self-transformation involve beliefs and ensuing actions which although (initially) inadequately grounded, might successfully motivate the formation of well-founded beliefs. What is peculiar about such belief formation in these cases is that the normal flow of causation is reversed. Under normal circumstances, an already independently established belief together with a desire lead to and explain an action. Here it is action on the basis of a bogus belief which establishes an authentic belief indistinguishable from its counterfeit predecessor.

(9) Amélie Rorty's claim that there may be rational grounds for acquiring a disposition whose exercise is often irrational seems to be apposite here. In (1988: 200), she argues that, "It might be appropriate and desirable to have the capacity for and even to develop the disposition to certain fears, knowing that they will sometimes involve rash and inconsiderable beliefs and actions".

(10) Nonetheless Nozick shies away from endorsing the view that a belief insensitive to the evidence (even when differentially or selectively so) might be considered the rational thing to believe. Even where in particular cases believing falsehoods has demonstrably better consequences than believing truths, it would be better to adopt a principle discouraging such beliefs, since (1) believing falsehoods generally brings disutility in its train; (2) the rationality of a belief depends on the network of reasoning in which it is embedded, which means that the addition of any particular belief has implications for the others — introducing a false belief may undermine the overall explanatory unification of one's beliefs.

(11) There are interesting arguments for the rational preferability of certain forms of evidence-avoidance. Davidson (1985: 143) seems to endorse such conduct in certain cases: "It is neither surprising nor on the whole bad that people think better of their friends and families than a clear-eyed survey of the evidence would justify. Learning is probably more often encouraged than not by parents and teachers who overrate the intelligence of their wards". Rawls's (1993) account of "public reason" includes the justification of a policy of disallowing certain kinds of considerations from entering collective decision-making (and draws on an analogy with fair procedure in courts of law, where certain evidence is excluded in the service of protecting and paying due regard to other values, e.g. individual rights). But there is still the nagging doubt about whether a principle that sanctions such avoidance is rationally justifiable, and about the stability of the corresponding strategy (which surely trades on the risk that the excluded evidence will not surface or be invoked).

(12) It is possible that some of the tensions outlined above could be resolved in the light of an account that distinguished clearly between different norms of rationality. The appeal to reasons occurs in a variety of contexts, sometimes with the intent of explaining, at others with the intent of justifying, beliefs, actions, and so on. It could be that the norms involved in these different contexts are significantly different, and this would account for the fact that we feel pulled in different directions in considering irrational phenomena.


Baier, Annette. 1994/5. Moral Prejudices. Essays on Ethics. Cambridge, Mass.: Harvard University Press.

Bratman, Michael E. 1987. Intention, Plans, and Practical Reason. Cambridge, Mass.: Harvard University Press.

Davidson, David. 1982. "Paradoxes of Irrationality", in R.Wollheim and J. Hopkins (eds) Philosophical Essays on Freud: 289-305. Cambridge: CUP.

——— 1985. "Deception and Division", in E. LePore and B.P. McLaughlin (eds) Actions and Events. Perspectives on the Philosophy of Donald Davidson.

Dunn, Robert. 1995. "Motivated Irrationality and Divided Attention", Australasian Journal of Philosophy 73,3: 325-335.

Elster, Jon. 1989. Solomonic Judgements. Studies in the Limitations of Rationality. Cambridge: CUP.

Johnston, Mark. 1995. "Self Deception and the Nature of the Mind", in C. MacDonald and G. MacDonald (eds) Philosophy of Psychology. Debates on Psychological Explanation: 433-460. Basil Blackwell.

Nozick, Robert. 1993. The Nature of Rationality. Princeton: Princeton University Press.

Rawls, John. 1993. Political Liberalism. New York: Columbia University Press.

Rorty, Amélie. 1980. "Where Does the Akratic Break Take Place". Australasian Journal of Philosophy. Vol. 58, No. 94: 333-346. in Action. Essays in the Philosophy of Mind. Boston: Beacon Press.

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