ABSTRACT
In recent years, a number of researchers in the psychology of thinking, reasoning and decision making have advocated “dual process” theories of cognition (Evans, 2003). It is suggested that people’s behaviour reflects the operation of two distinct thinking systems. Moreover, these systems interact in a complex way and often appear to be competing to control behaviour. Such theories have become increasingly popular in recent years and are now being applied in the field judgement and decision making (Gilovich et al., 2002; Hammond, 1966; Kahneman and Frederick, 2002) as well as in the psychology of reasoning (Evans and Over, 1996; Sloman, 1996; Stanovich, 1999; Stanovich, 2004). However, the term “dual process” is a label used for historical reasons that disguises an important distinction, that between dual processes and dual-systems. Stronger forms of the theory (Evans and Over, 1996; Reber, 1993; Stanovich, 2004) propose that the dual processes are rooted in two distinct cognitive systems that have sharply differing evolutionary histories and neurological substrates (Goel, 2005).
