It is a very old conjecture that emotion governs human choice. Early philosophers like Epicurus (trans. 1993) and Aristippus of Cyrene (see Parry, 2014) appear to have held this assumption, often described as "psychological hedonism" (see Overskeid, 2002).British thinkers of the 18th and 19th century were among the most important exponents of psychological hedonism. In a well-known dictum, Bentham (1823, p. 1) left little doubt as regards his own view: "Nature has placed mankind under the governance of two sovereign masters, pain and pleasure. … They govern us in all we do, in all we say, in all we think …" Famously affirming that human rationality or reason could never on its own control behavior, Hume (1739) was equally clear. Indeed, he claimed (p. 413) that reason "can never oppose passion in the direction of the will." Instead, said Hume (p. 415), "Reason is ... the slave of the passions, and can never pretend to any other office than to serve and obey them."In the second half of the 20th century, psychologists and neuroscientists tended (with some exceptions, such as Toda, 1980) to stay away from the question of how reason and emotion interact to govern human conduct. Important in turning the tide, however, helping researchers see the role of emotions in thinking and decision making, were Damasio and his co-workers (e.g., Bechara, Damasio, Tranel, & Damasio, 1997;Damasio, 1994). Damasio (e.g., 1994) argued convincingly that there is no necessary conflict between ...