We think in two modes

Humans have two basic modes of thought:

System 1

System one operates automatically. Doing fast calculations and quick judgments. System one is imperfect. Snap Judgments are from System 1.

System 2

System two is calculating, but fundamentally lazy. Following Checklists or procedures requires engaging system 2.

Each mode has its purpose, its strengths, and its weaknesses. See their respective notes.


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