The Duality of the Mind: The Fluctuations of Judgment Played by System 1 and System 2 (January 2026) System 1 and System 2 are two distinct functions that underpin human thought. System 1 is intuitive and reacts rapidly, processing most everyday judgments instantly. However, it tends to rely on partial information, filling in the narrative through association and misconnecting causal relationships. For example, it is susceptible to the anchoring effect, where judgments are drawn toward recent events or simply presented numbers. While speed and automaticity are System 1's strengths, accepting its judgments uncritically can lead to misunderstandings and biases.

The Duality of the Mind: The Fluctuations of Judgment Played by System 1 and System 2 (January 2026) System 1 and System 2 are two distinct functions that underpin human thought. System 1 is intuitive and reacts rapidly, processing most everyday judgments instantly. However, it tends to rely on partial information, filling in the narrative through association and misconnecting causal relationships. For example, it is susceptible to the anchoring effect, where judgments are drawn toward recent events or simply presented numbers. While speed and automaticity are System 1's strengths, accepting its judgments uncritically can lead to misunderstandings and biases.
In contrast, System 2 possesses the capacity for slow, deliberate thinking. It reviews System 1's judgments and serves to correct errors. Actions like taking time to think during negotiations, comparing multiple options, or questioning whether one is being swayed by numbers are signs of System 2 at work. However, System 2 requires concentration and energy, making it difficult to operate constantly. Therefore, it must be consciously activated during important decisions or situations involving significant value.
These two systems are not in conflict; they complement each other to shape our decision-making. Appropriately utilizing the speed of System 1 and the analytical power of System 2 leads to more accurate and calm thinking. According to Kahneman's research, many of our judgments are unconsciously influenced by System 1. Understanding its characteristics is key to improving the quality of our everyday decisions.