Both the economic and the minimal conception of rationality deal with their own problems. Whereas the economic conception is too demanding to be a plausible account of what rationality entails, the minimal conception is too formal. Someone who wants to commit a murder and believes in voodoo is minimally rational if he sticks needles into a puppet (Elster 1983: 3). This, however, goes directly against the grain of everyday intuitions, according to
which something is wrong with such beliefs (and perhaps also with such preferences). Instead of using vague intuitions as the ultimate bedrock on which to ground more demanding conceptions of rationality, I aim to base them on explicit, philosophical grounds.
By adding more requirements, I want to give more substance to the concept of rationality. The resulting conceptions limit the range of phenomena that can be understood as rational but not in the same direction as the economic conception. While this reduces the explanatory scope of the concept, it enhances its explanatory power (Moser 1990: 421). This way, it avoids the danger of turning rationality into a completely empty notion that can rationalize each action by referring to reasons that justify that action. In what follows, I will first develop a broad conception of rationality, which is primarily based on remarks from Jon Elster.
2.1. The level of actions and the relation with their reasons
The basic thrust of moving from a minimal to a broad conception of rationality is that actions should no longer be based on mere reasons but on good reasons. The extra conditions imposed by the broad conception of rationality are thus situated primarily at the level of the reasons themselves. The irrationality of a person sticking needles in a puppet is located at the level of his beliefs (it is irrational to believe that one can kill someone this way) and perhaps his preferences (it is irrational to want to kill someone). When somebody acts on the basis of irrational beliefs or preferences, the resulting actions are irrational as well, but the source of this irrationality lies deeper. At the level of the relation between the actions and their reasons, I will thus hold on to the requirement of intentionality, which was the core of the minimal conception of rationality.
2.2. The level of the reasons themselves: beliefs
People are not just ‘automata’ that select the action that best satisfies their preferences according to their beliefs, they are also concerned whether their preferences and beliefs are justified. To evaluate whether this is the case, one can refer to the ways these arise and change. In this respect, Elster (1983: 15- 26) stipulates that beliefs should be well-informed and that preferences should be autonomous. The main source of irrationality at this level is that of irrelevant causes bypassing reasons. The resulting beliefs and preferences “are
shown to be irrational if they are explained by mental causes that are not reasons for them” (Davidson 1982: 299). The broad conception of rationality thus leaves the assumption of exogenously given reasons, which dominates the economic conception of rationality. Instead, it analyzes whether the formation process of reasons satisfies certain standards.
Boudon (1993: 5) argues that it is crucial to construct a conception of rationality that can be applied to beliefs, since all actions are ultimately based on beliefs about the way the world works. As I have suggested, one needs specific requirements to speak of rational beliefs, because believing in a theory cannot be explained instrumentally. Even though beliefs are not instrumentally formed, they can be based on good reasons. The broad conception of rationality thus refers to the central notion of reasons as well. It stresses that beliefs are rational if they are supported by reasons that make them credible and arise from processes that reliably produce true beliefs (Nozick 1993: 64, 176).
To develop all this more fully, I want to refer to the work of Jon Elster. He argues that the information and cognitive processes available to the individual are crucial to speak of rational beliefs. Instead of requiring these to be perfect – as the economic conception does – Elster (1983: 16; 1986: 13-14) argues that beliefs should be properly grounded in and derived from the available information. A belief is rational in the broad sense when it is well-informed and based on a sound judgment of the available information. Beliefs that go against the available evidence are clearly irrational. To get a better grip on what this exactly means, it is useful to proceed ‘ex negativo’. To summarize, beliefs are broadly irrational when they “are generated by belief-irrelevant causal processes, i.e. causal processes where the causes include not only reasons” (Elster 1979: 130). One can distinguish between two categories of broadly irrational beliefs. A first category consists of beliefs arising from cognitive defects. Evidence from experimental economics convincingly shows that people rely on heuristics to assess probabilities. While these are quite useful in general, they sometimes lead to cognitive errors (Moser 1990: 171). Take the case where people are asked to estimate the odds that a Third World War will break out in the next year. If the options are ranked from zero to hundred percent, the average answer will be lower compared to when one ranks them from hundred to zero percent (Elster 1989a: 34-35). Here, one can speak of an unsound judgment and thus of a broadly irrational belief. Another factor that can cause a cognitive bias in belief formation processes is the tendency of people to attach more importance to concrete than to abstract information. Unemployed people, for example, tend to overestimate the unemployment rate, while employed people tend to underestimate it (Nisbett & Ross 1980: 19). Vivid
information, which is emotionally laden or close in time and space, is likely to have a greater weight on the formation of beliefs (Nisbett & Ross 1980: 43-51). Here too, there is a lack of sound judgment, which can be defined as the capacity to process the available information without attaching excessive importance to a particular part of it (Elster 1983: 16). These examples show that one can be rational in the minimal sense – as long as beliefs are consistent with other beliefs – but irrational in the broad sense.
A second category consists of beliefs that are improperly influenced by volitional urges. Here, the best example is that of wishful thinking, which means that individuals believe things to be as they want them to be (Elster 1983: 148; Elster 1989a: 37-38). Since the available information is distorted by an irrelevant motivational bias, such beliefs are rightly called irrational. This defect in the belief formation process forms the main culprit of an individual’s irrationality.
2.3. The level of the reasons themselves: preferences
A broad conception of rationality also adds requirements at the level of preferences. Next to the formal conditions of consistency, transitivity and egocentrism, it stresses that preferences should be autonomously formed. Here too, Elster (1983: 22) proceeds to define autonomy ‘ex negativo’ by referring to those preferences that are surely heteronomous and thus irrational in the broad sense of the word. Heteronomous preferences are formed by processes over which the person has no control: “in such cases the individual is in the grip of causal forces operating ‘behind his back’ and governing his preferences in a way that he does not himself understand” (Elster 1979: 148). This is clearly irrational: “one cannot be rational if one is the plaything of psychic processes that, unbeknownst to oneself, shape one’s desires and values” (Elster 1989b: 6). I want to distinguish between two kinds of distorting influences. First, there are extra-mental circumstances that can have an impact on an individual’s preferences beyond his control. Examples are adaptive preferences (I prefer something simply because it is available) and counteradaptive preferences (I prefer something because it is not available). The exemplary case of the former is La Fontaine’s story of the fox that no longer prefers the grapes – which he believes to be sour – simply because they lie outside his reach (Elster 1983: 109-140). The logic of the latter is captured in the saying that “the grass is always greener at the other side of the fence” (Elster 1989a: 8-9). Other examples are conformism (I prefer something simply because others do so as well), anti-conformism (I prefer something simply because others do not),
novelty (I prefer something simply because it is new to me) and inertia (I prefer something simply because it was already there for me) (Elster 1989b: 6).
Second, there are mental forces that have an impact on an individual’s preferences beyond his control. Here too, one can distinguish between a cognitive and a motivational bias. First, empirical findings from experimental economists show that changes in the way equivalent options are framed cause preferences to shift (Tversky & Kahneman 1981: 453). Second, preferences can be distorted by underlying volitional forces or urges. For example, someone who wants to quit smoking can be overwhelmed by a visceral craving for nicotine. The irrationality of his longing for a smoke lies in the fact that his preference ordering is influenced by unconscious and irresistible drifts and thus changes without any reason whatsoever.