ABSTRACT
In chapter 4, three tasks from the heuristics and biases literature displayed large individual differences in cognitive ability between those who solved the problem and those who did not. One possible interpretation of the consistent pattern across these three problems is in terms of two-process theories of reasoning (Epstein, 1994; Evans, 1984, 1996; Evans & Over, 1996; S. A. Sloman, 1996). For example, Sloman distinguished an associative processing system with computational mechanisms that reflect similarity and temporal contiguity from a rule-based system that operates on symbolic structures having logical content. The key feature that signals the operation of both systems in a reasoning situation is that of simultaneous contradictory belief-CIa feeling or conviction that a response is appropriate even if it is not strong enough to be acted on" (Sloman, 1996, p. 11). Certainly such a conflict can be said to be present for the 50.4% of the subjects who responded identically to both versions of the Tennis Problem despite viewing them as subjectively or objectively different (and the 64.6% who did so in the Movie Problem).
