The speed of thought determines our destiny. Two minds intersect.

The speed of thought determines our destiny. Two minds intersect.

Daniel Kahneman clearly demonstrated that human thinking is not uniformly rational with two systems, System 1 and System 2. System 1 is intuitive, works fast, requires no effort or awareness, and is responsible for the majority of everyday decisions. System 2, on the other hand, is slow and conscious, performing logical thinking, calculations, and careful judgments, but it consumes a great deal of concentration and mental energy and does not always operate.

This dual structure often causes humans to make systematic errors in judgment, called biases. It is important to note that bias does not stem from emotional weakness, but from the design of cognition itself. In particular, in probability judgments, impressions and similarities are prioritized over statistical facts, and the reference rate is easily ignored. Examples such as the Müller-Lyer illusion, in which the error is understood but not corrected, are a clear example of the strength of the automaticity of System 1.

This book does not deny intuition, but rather demonstrates the need to understand its limitations and then consciously engage System 2 in critical situations. Human decision making is shaped by the tension between speed and deliberation.