Two systems of reasoning: architecture and relation to emotion.

Distinguishing cognitive systems that support intuition and deliberation has proven necessary to explain how people reason,1, 2 decide,3 categorize,4 form attitudes,5 make confidence6 and moral7 judgments, and prioritize goals.8 Both behavioral and neuroimaging evidence show that the evidence supports similar distinctions in each field. Deliberative processing enlists working memory, and intuitive processing depends more directly on long-term memory retrieval. One of the key unanswered questions concerns how the systems interact. The data suggest that one of the key functions of deliberation is to suppress intuition. It does not invariably succeed, however, and leakage is common. Another question concerns the relations between affect and reasoning systems. The evidence suggests that emotions are not exclusively related to the intuitive system. Instead, emotional reactions that are directly tied to the perception of objects and events (e.g., fear) are associated with intuition, emotions that arise when alternative possibilities are considered (e.g., regret) are tied to deliberation, and moods (e.g., happy, sad) influence how much each system is relied on.