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Philosophy of Action

How Genuine is the Paradox of Irrationality?

Yujian Zheng
Lingnan College, Tuen Mun, Hong Kong

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ABSTRACT: In light of interpreting a paradox of irrationality, vaguely expressed by Donald Davidson in the context of explaining weakness of will, I attempt to show that it contains a significant thesis regarding the cognitive as well as motivational basis of our normative practice. First, an irrational act must involve both a rational element and a non-rational element at its core. Second, irrationality entails free and intentional violation of fundamental norms which the agent deems right or necessary. Third, "normative interpretation" is only possible for objects that are both natural events and capable of mental operations which presuppose some freedom of will as well as constructive representation of the surrounding reality. Fourth, there is always a question of whether we strike the best balance between fitting individual mental items consistently with the overall behavior pattern and keeping our critical ability in following certain normative principles which constitute our rational background. Fifth, the paradox of irrationality reflects and polarizes a deep-seated tension in the normative human practice under the ultimate constraints of nature. Finally, the ultimate issue is how we can find the best lines on which our normative rational standards are based-"best" in the sense that they are close enough to limits of human practical potentialities and are not too high as to render our normative standards idle or even disastrous.

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In "Paradoxes of Irrationality," Davidson has the following remark, which arises from, but is not limited to, the explanation of weakness of will:

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 of rationality needed to justify any diagnosis at all. (1)

Many theorists who try to provide an adequate explanation of weakness of will and its bearing on the issue of rationality fail to fully appreciate the implication of the above remark, which I believe is an important thesis for any attempt to understand the source of many apparent puzzles around akrasia. Perhaps this failure is partly due to the fact that Davidson himself does not make it clear how central this thesis will be for exploring the cognitive as well as motivational basis of our normative practice. In this paper, I shall discuss in section I the conceptual ingredients of being irrational, viz., its relation to reason and to normativeness; in section II I shall come to direct grips on the possible paradoxical elements in explaining the irrational, and some notions about the specialties of mind and its interpretation will be discussed thereby. My conclusion is that the paradox of irrationality reflects as well as polarizes a deep-seated tension in the normative human practice under the ultimate constraints from nature.


When we judge or criticise some action as irrational, it does not necessarily mean that this action is unintelligible or paradoxical in its own nature. We can be perfectly aware of the normative standard of our criticism and know, or be able to conceive, the reason why such an action took place. For instance, we can understand why someone failed to quit smoking despite his resolution and still think that he is irrational for doing, or undoing, it. We need not know the exact details of its underlying causal mechanism to make the criticism. Our judgment of irrationality could be a simple matter of normative position we adopt towards certain behaviours which we believe could be corrected through personal endeavour. Irrationality does not seem to have a necessary connection with being paradoxical, at least in our normal use of everyday language.

Neither is it necessarily paradoxical if we cannot explain in causal terms the psychological mechanism of weakness of will if we grant that the phenomenon is genuine. For in the domain of natural sciences, people often face difficult phenomena that defy explanation in our present theories for quite long time and we never thus regard them as paradoxical.

When we see someone who we believe has basic mathematical ability writes on a chalkboard "2x2=3," our first reaction must be some judgment like the following: "either he made some mistake absent-mindedly or he is not doing math here (e.g., the symbol 'x' does not stand for multiplying)." If, on being queried, he insists that he is doing math and every symbol carefully written here has the normal meaning as everybody understands it and he knows that 3 is the wrong product of 2x2 but he does it anyway, then we may have a puzzle. We still do not believe that there is really such people who are normal in every other respect or on most other occasions but freely and knowingly do such a blunt wrong computation.

Were we to grant the existence of such acts, we might call them "irrational" in the sense of intentional violation of a certain fundamental norm that the agent himself deems correct. But in the hypothetical case I have just stated, I do not think that reasonable people will readily grant it such an irrational status. For we find it unintelligible or impossible to have a simple contradiction like this at the level of pure (theoretical) reason. We will speculate instead that the person may have some other motive or reason to do this, e.g., he wants to confuse people on the spot or mislead young kids who have not learnt much math yet, and he may have further reasons for such confusion or misleading, etc. Now we have entered the domain of practical reason. In light of these underlying practical reasons this person has or holds, we may re-evaluate the rationality of his odd act mentioned above. If we take whatever motives he has as given, then it is likely that his present act is rational in the sense of being a best means to the given ends. If we want, however, to further examine these motives themselves in the light of his global interests, we, perhaps as well as he himself, may find that they are not the best reasons concerning his present act. All things considered, he has a better reason not to so act. If he really knows this but nevertheless acts against his best judgment, then we have a genuine case of irrational behaviour. And only here "irrationality" properly applies.

Irrationality is a failure within the house of reason, says Davidson. (2) That is, if the person never engages himself in relevant reasoning, he cannot be judged irrational; we may call him nonrational at most. Though the irrational must not lie totally outside the ambit of the rational, it must not lie totally inside either. "Totally inside" means that everything involved in the putatively irrational behaviour has an explicit or implicit reason explanation which seems so good as to "turn it into a concealed form of rationality," or, in other words, the actor himself may, but not necessarily does at the moment of action, appeal to such reason explanations to justify his apparently irrational behaviour. "What is special in incontinence is that the actor cannot understand himself: he recognizes, in his own intentional behaviour, something essentially surd." (3) This challenges us to explain a certain kind of putatively irrational behaviour without thereby rendering that very behaviour subjectively rational—i.e., from the actor's own point of view, his action is irrational, no matter at the moment of acting or later when he has more time to reflect upon it. So something must be partially outside the ambit of reason that has done the job of irrationality. Davidson seems to follow this line of thought when he begins to appeal to a partitioning model of mind and claims that reason has no jurisdiction across the boundary. (4) Interestingly enough, however, many theorists have tried to point out that Davidson's treatment of incontinent actions in reconciliation with his principles governing the relationship between reasoning and acting is unsuccessful, even on his own terms, (5) and intellectualistic, viz., focusing too much on the cognitive powers such as reasons and judgments and thus neglecting the role of conative powers in motivating such actions. (6) Although such criticisms have not yet touched the paradoxes of irrationality, it is important, at this point, to note that irrationality, if there is any, seems to occur only when conative factors come into relations with reason, i.e., only when it is not a pure matter of (cognitive) reasoning.

Davidson names the following view the Plato Principle: no intentional action can be internally irrational, in the Socratic sense that no one willingly acts counter to what he knows to be best. (7) This principle is controversial and even paradoxical in the face of so many apparently akratic acts in our daily life. But from the above example we can see that if we limit the "action" in the Plato Principle to theoretical acts or reasoning only, it will not be controversial at all. (8) This may mean that the proper domain for something like, or in the spirit of, the Plato Principle is a theoretical or cognitive one; (9) it would be too strong or unrealistic to sanction such a principle in practical domain that characteristically involves various conative and volitional factors. (But one may wonder why conation or volition would make such a difference.) It is interesting to notice that the above expression of the Plato Principle sounds like it is a pure description of a natural fact, i.e., everybody by nature acts (reasons) intentionally according to what he knows to be best (closest to truth). But this is plainly wrong. Even within the domain of pure cognition, people could freely and consciously deviate from what he knows to be best if there were no learnt norms governing reasoning process. The reason why we almost never see people intentionally violate the logic rules in their reasoning if they ever understand them is not because Logic is ingrained in our brain but rather because we were brought up in such a natural and social environment in which both the collective human praxis and individual activities cannot go very far without certain fundamental epistemic norms. "Our acceptance of epistemic norms, at any rate, is explicable practically: by and large we benefit from proportioning belief to evidence." (10) The ultimate constraints come from nature, no matter directly (in individual encounters of external as well as internal nature) or indirectly (through socially sanctioned and mediated norms). Epistemic norms are already part of our second nature. So the Plato Principle, regardless of its legitimacy scope, must be a normative principle whose proper function is not to describe or predict, but to prescribe or direct. Only when we are made fully aware of the normative nature of those basic principles or requirements in our justifiable practice do we embark on understanding the distinctiveness as well as intricacies of the Davidsonian paradox of irrationality raised at the very beginning of this paper.


Let us summarize the basic points we have reached so far. First, the irrational acts, just like all intentional actions, must involve both a rational element (viz., appealing to reasons) and a nonrational element (viz., being susceptible to non-reasons) at the core; short of either element we will not have irrationality. Second, irrationality entails free and intentional violation of fundamental norms which the agent himself deems right or necessary. This means both that the criteria we use to judge the irrational are normative (no matter how natural we instinctively feel they are) and that irrational behaviours are correctable (viz., the nonrational part is controllable), so do we seem to believe at least.

What is paradoxical in all of these then? Davidson provides no further explication except the very passage I quoted in the beginning. Let us examine it a bit more closely.

The two horns that purportedly make the paradox is this: if we explain too well how weakness of will is possible, i.e., if we find a causally and mentally too coherent picture for it, we turn it into a concealed form of rationality; while if we assign incoherence too glibly, i.e., if we exclude akrasia from the class of intelligible phenomena (for incoherence breeds unintelligibility), then we merely mystify the otherwise understandable (thus rationally diagnosable) human behaviour by giving up the always possible effort of successful interpretation of the other. Put in this way, it sounds more like some hermeneutic dilemma. But sceptics may question the genuineness of this kind of paradox. What is the demarcation between explaining appropriately and explaining "too well?" If coherence is the objective of our interpretation and explanation, how can it be criticised as too coherent? On the other hand, if someone fails to understand a difficult or complicated phenomenon because of his laziness or incompetence yet excuse himself by blaming the object for incoherence, that is not puzzling at all and should be simply prohibited. If we have no doubt about the fundamental coherence of nature, why not stop assigning any incoherence to human nature as well? Then what you are left to do is try your best to get as coherent explanations as possible for any human phenomena. Where is the sting of the paradox here?

The answer seems to be that only a certain special kind of difficult phenomena constitute paradoxes for our explanation. More specifically, only when a phenomenon involves both causal as well as mental properties is it possible to have paradox of the kind Davidson has exposed. A psychological event can be both causal and mental at the same time, meaning that it can be described in both neurophysiological (and ultimately physical) terms and in terms of its propositional content or logical relations to other events with propositional contents. But before we get to any detailed picture of the relationship between mental and non-mental/causal terms, there is much conceptual work to do. What is special about mind is not just that it creates and understands meanings, i.e., has certain mental states or events with propositional contents, but also that the mental states such as belief, desire, reason, judgment, want, will, volition, emotion, etc., do not have clear conceptual boundaries between themselves—they normally overlap, interweave and change into one another. What this implies for the issue of diagnosing irrationality is that we have enough manoeuvring room for either explaining (rationalizing) or dismissing (ruling out) whatever puzzling phenomena as we find exigent. Such manoeuvring room or freedom in our interpretations is made possible by lacunas, overlaps and fuzzy or grey areas among these conceptualized mental items in linguistic forms. Precisely because of this kind of inevitable conceptual leeway, we always have a choice between assigning this or that level of coherence to this or that part of mind with corresponding propositional contents or logical relations. Hence there is always a question whether in mapping out mind in a certain way we strike the best balance between fitting individual mental items with the overall observable behaviour patterns on the one hand, and keeping our critical ability in following certain fundamental normative principles, which constitute our contemporary rational horizon, on the other hand.

But, again, where exactly does the paradoxical element lie? The degree of rationality a person has, according to common sense, seems to be some inherent property of his, which can thus never be dependent upon the third-person view of his behaviours. At least in any particular moment of his life, it seems to be a fixed fact about his mental capacities or tendencies that he exhibits certain general patterns of thinking and motivating. Without disputing this, how can we then make sense of the claim that the interpreter is entitled to assign a certain degree of coherence/rationality to the person being interpreted? (11) In other words, is it not paradoxical to say that some independent fact of one mind is dependent upon another mind's decision to, or how to, understand it? In the final analysis, the underlying paradox of irrationality in understanding another mind is not a paradox in and of the object itself, but rather a paradox of the normative interpreting relationship between the subject and the object which are of the same kind in a fundamental sense. The thrust of exposing such a paradox is to reveal some largely hidden tension between two seemingly legitimate yet mutually exclusive requirements, namely between the requirement for objective description and that for normative evaluation. Interpretation or explanation is purportedly targeting at some existing and fixed phenomenon and is thus truth-oriented and descriptive at its core whereas normalization concerns solely the standards we have adopted or agreed upon and is thus compliance-oriented and conventional. Therefore, simply mixing these two together in one act may look apparently contradictory, though in a somewhat trivial sense. This is not the case, however, for the original Davidsonian expression of the paradox. It does not directly involve the terms such as "descriptive" and "normative"—this gives it some advantage of avoiding blunt but trivial contradiction; neither does it necessarily imply a reading based on the distinction and possible connection between the descriptive and the normative—this, however, conduce to its obscurity or its mystifying effect on a potentially very significant theme.

Normative interpretation is only possible, as well as necessary, (12) for objects that are both natural events, which are subject to physical laws and the constraints from brute nature, and capable of mental (propositional and volitional) operations which presuppose some freedom of will as well as constructive representation of the surrounding reality (be it natural or social). Persons or minds are such objects. Normative interpretation is not simply equivalent to interpretation with norms; the latter could mean something very basic and uninteresting, i.e., any interpretive sentence, just like others, has to be governed by certain linguistic or logic rules which make meanings (human understanding in general ) possible. Here we are talking about certain normative acts at a higher level. Although normative interpretation must be involved in most, if not all, descriptions of human behaviours, its seemingly paradoxical element, or internal tension, does not show except in certain exceptional or extreme cases, cases which apparently involve unintelligible, "irrational" (in the normal sense of the word) behaviours. Weakness of will is the paradigmatic example of a large class of such behaviours. In explaining the possibility of these behaviours, we inevitably face a choice, somewhere in the way of pursuing almost endless ramifications, of either ending up resolutely with certain more or less satisfactory solution (leaving some explanatory residues or loopholes) and keeping our normative ground for criticism somewhat standing, or yielding all the way to an attractive scientistic dogma that everything happened (regardless of physical or mental status) must have a sufficient naturalistic explanation, viz., in causal and evolutionary terms at every possible level. Put in another way, something undeniably natural is drastically up to us to decide its existence and/or place in our normative mapping of reality.

I shall conclude this paper by considering a hypothetical scenario. Suppose we take the relentless naturalistic gesture, and also grant that luckily we already have a near perfect scientific model of mind—e.g., we can explain every relevant behavioristic aspect of the real case of weakness of will in terms of experimentally well-grounded concepts or variables; and moreover, such a model fits very well with various animal behaviours and the best evolutionary picture we have about life. Then what possible misgivings will Davidsonian theorists have about such an explanation? If the answer is that it turns the putatively irrational phenomena into a concealed form of rationality, one may further question whether the imputation of irrationality is not fully justifiable in the first place. Some moves of this type have made by insightful philosophers against the Davidsonian as well as common-sense verdict of irrationality on all akratic acts. (13) Nevertheless, one can hardly deny the necessity, and even uniformity on certain occasions, of judging some behaviours as irrational in any human society. The ultimate question in this direction is perhaps how we can find the best lines on which our normative rational standards are based, "best" in the sense that they are close enough, at every given moment of human evolution, to limits of human practical potentialities and they are not too high (overestimating human capacities) as to render our normative standards idle or even disastrous. The significance of Davidson's paradox of irrationality, albeit its imperfect form of expression, lies exactly in its power of challenging us to explore as relentless as possible where such limits or best lines are.

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(1) Donald Davidson, "Paradoxes of irrationality," Philosophical Essays on Freud, eds. R. Wollheim and J. Hopkins (Cambridge University Press, 1982) 303.

(2) Ibid. 289.

(3) Donald Davidson, "How is Weakness of the Will Possible?" Moral Concepts, ed. J. Feinberg (London,1969) 113.

(4) See Donald Davidson, "Deception and Division," Essays on Actions and Events (Oxford: Clarendon Press, 1980).

(5) See, for example, Joseph Margolis, "Rationality and Weakness of Will," Journal of Chinese Philosophy 8 (1981): 9-27.

(6) See Kirk Robinson, "Reason, Desire, and Weakness of Will," American Philosophical Quarterly 28 (October 1991): 295-6; and Robert Audi proposes, instead, a wider, holistic and non-intellectualistic conception of rational action in his "Weakness of Will and Rational Action," Australasian Journal of Philosophy 68 (September 1990): 276-81.

(7) See Davidson, "Paradoxes of irrationality" 294.

(8) One might still argue that there are incontinent beliefs as well as incontinent actions; and the former, unlike the latter, belong to cognitive/theoretic domain only. How does the Plato Principle accommodate this? A simple answer is that even the belief against one's best evidentiary judgment is normally caused by some underpinning desires or wishes which are outside of, and not invoked as reasons in, the pure cognitive/theoretic domain. For various discussions about this, see David Pears, Motivated Irrationality (Oxford University Press, 1984) Ch.9; and Alfred Mele, Irrationality (Oxford: Oxford University Press, 1987), Ch. 3; John Heil, "Minds Divided," Mind 98 (October 1989): 574-581.9 According to Davidson, Carnap and Hemple have argued for a principle which all rational people will accept though it is no part of the inductive logic. It is the requirement of total evidence for inductive reasoning: give your credence to the hypothesis supported by all available relevant evidence. See Davidson, "How is Weakness of the Will Possible?" 112.

(10) Heil, op. cit. 580.

(11) This expression certainly allows for the possibility that the interpreter and the interpreted are one and the same person, i.e., one wants to understand himself.

(12) In the sense that there would not be human beings and their societies were there no normative practice at the very core and beginning of homo evolution.

(13) See Audi, op. cit. 275, 278.

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