── ── Cognitive bias
Dual-System Thinking (System 1 / System 2)
Two parallel modes: System 1 — fast, automatic, effortless (pattern recognition, gut feel). System 2 — slow, deliberate, effortful (analysis, computation, critical evaluation). System 1 runs ~95% of decisions by default; System 2 engages only when recruited. Most cognitive biases are System 1 shortcuts misapplied where System 2 should have intervened.
Run Dual-System Thinking (System 1 / System 2) on a real problem
Bring something you're actually deciding — free, in the browser.
How it works
Step 1 — Identify decision + initial answer: note what comes to mind quickly, your confidence, and time-to-answer.
Step 2 — Classify system: quick + automatic + confident + no felt effort = System 1; slow + deliberate + uncertain + felt effort = System 2.
· Stakes · Familiarity · Recruit System 2? · · --- · --- · --- · · Low · High · No · · Low · Low · Optional · · High · High · Yes (verification needed) · · High · Low · Mandatory ·
When to use it
- a decision feels obvious but the stakes are high
- someone says 'I just trust my gut' on a consequential call
- a team is converging fast without pushback
- you're tired or pressured and still need to decide
- you're in an unfamiliar domain moving on instinct
When not to use it
the decision is genuinely routine and low-stakes; you have well-trained calibrated expert intuition in that exact domain and need to act fast.
Worked example
Kahneman 2011 + 40 Years of Tversky-Kahneman Research
The framework's empirical foundation is the Tversky-Kahneman research program, which began in 1969 at Hebrew University in Jerusalem and continued until Tversky's death in 1996. The program produced ~30 major papers, documenting one cognitive bias after another, each time with the same structure: a specific intuitive judgment that subjects make confidently, but that diverges systematically from rational or statistical analysis.
Install this skill (free, MIT)
npx skills add deciqAI/knowledge-skillsUseful? Star the repo — stars help other builders find it.
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