Keith Stanovich on Rational ThinkingBringing together the findings of years of research, Keith Stanovich, a professor of human development and applied psychology at the University of Toronto, has just published an accessible account of why high intelligence, as measured by intelligence tests, does not guarantee highly rational thinking.
In What Intelligence Tests Miss: The Psychology of Rational Thought, Stanovich defines rationality as the combination of
- adopting appropriate goals
- taking appropriate action, given one's goals and beliefs
- holding beliefs commensurate with available evidence
- the autonomous mind "gut reactions." More specifically, the autonomous mind produces affective responses to situations (e.g., anger at being cheated), previously learned responses that have become automatic (e.g., steering automatically in the direction of a skid on an icy road), conditioned responses (e.g., feeling better after taking a pill even if it's a placebo), and "adaptive modules that have been shaped by human evolutionary history" (e.g., face recognition). As its name suggests, this component of thinking operates without conscious attention. However, it can be consciously overridden by the algorithmic mind if prompted to do so by the reflective mind (see below).
- the algorithmic mind takes in information (which may or may not be accurate and may or may not be classified correctly) and responds according to a conscious thought process analogous to running of a computer program. The response is fully appropriate if it optimally helps achieve a rationally chosen goal (arrived at through reflective thinking see below). The information processing carried out by the algorithmic mind can be applied to both real and hypothetical situations. A person's efficiency in using the algorithmic mind is reflected in his/her IQ score.
- the reflective mind chooses goals, relates goals to beliefs about the world, tests beliefs against evidence, and chooses action that is optimal given the aforementioned goals and beliefs. Determines when hypothetical thinking is needed to evaluate a situation and make a decision. A person's effectiveness in using the reflective mind is reflected in the degree of rationality of his/her behavior and decisions. The degree of rationality depends on the person's thinking dspositions, e.g., his/her procilivity for being actively open-minded. A key point is that variation in thinking dispositions is not perfectly correlated with intelligence.
... rationality is a more encompassing construct than intelligence. To be rational, a person must have well-calibrated beliefs and must act appropriately on those beliefs to achieve goals both properties of the reflective mind. The person must, of course, have the algorithmic-level machinery that enables him or her to carry out the actions and to process the environment in a way that enables the correct beliefs to be fixed and the correct actions to be taken. Thus, individual differences in rational thought and action can arise because of individual differences in intelligence (the algorithmic mind) or because of individual differences in thinking dispositions (the reflective mind). To put it simply, the concept of rationality encompasses two things (thinking dispositions of the reflective mind and algorithmic-level efficiency) whereas the concept of intelligence at least as it is commonly operationalized is largely confined to algorithmic-level efficiency. (p. 33)Stanovich adds:
It is important to note that the thinking dispositions of the reflective mind are the psychological mechanisms that underlie rational thought. Maximizing these dispositions is not the criterion of rational thought itself. Rationality involves instead the maximization of goal achievement via judicious decision making and optimizing the fit of belief to evidence. The thinking dispositions of the reflective mind are a means to these ends. Certainly high levels of such commonly studied dispositions as reflectivity [taking time to think before deciding what to do] and belief flexibility are needed for rational thought and action. But "high levels" does not necessarily mean the maximal level. One does not maximize the reflectivity dimension for example, because such a person might get lost in interminable pondering and never make a decision. Likewise, one does not maximize the thinking disposition of belief flexibility either because such a person might end up with a pathologically unstable personality. Reflectivity and belief flexibility are "good" cognitive styles (in that most people are not high enough on these dimensions, so that "more would be better"), but they are not meant to be maximized. (p. 35)À propos of the relation between intelligence and rationality, Stanovich says:
Not only is rational thought itself predicted by thinking dispositions after intelligence is controlled, but the outcomes of rational thought are likewise predicted by variations in characteristics of the reflective mind. (p.37)In sum, rationality requires:
- the mental abilities measured by IQ tests
- "mindware" learned rules, procedures, and strategies
- thinking dispositions that foster rational thought
Rational thinking errors appear to arise from a number of sources it is unlikely that anyone will propose a psychometric g of rationality. Irrational thinking does not arise from a single cognitive problem, but the research literature does allow us to classify thinking into smaller sets of similar problems. (p. 173)Stanovich devotes considerable attention to a taxonomy of cognitive deficiencies that impair rationality. These deficiencies include:
- lack of intellectual engagement
- cognitive inflexibility
- need for closure (as opposed to negative capability)
- belief perserverance in the face of contrary evidence
- confirmation bias
- Overconfidence in one's thinking and decision-making prowess
- Insensitivity to inconsistency