── ── Cognitive bias
Hindsight Bias
Hindsight bias — the "I knew it all along" effect — is the tendency, after learning an outcome, to misremember your prior judgment as having been closer to that outcome than it actually was. Fischhoff (1975) demonstrated three distinct components: memory distortion ("I said it would happen"), inevitability ("it had to happen"), and foreseeability ("anyone should have seen it"). Each…
Run Hindsight Bias on a real problem
Bring something you're actually deciding — free, in the browser.
How it works
Step 1 — State the outcome and the claim: outcome that occurred / who is being credited-blamed / claim of foreseeability (verbatim) / time elapsed.
Step 2 — Reconstruct the pre-outcome information set: what was knowable / what was genuinely uncertain / what contemporaneous records exist / consensus view at the time. Nixon test: if informed contemporaries gave the outcome ≤30%, "anyone should have seen it" is hindsight bias.
Step 3 — Decompose the three components: memory distortion (current memory vs. records) / inevitability (is outcome framed as the only possible result?) / foreseeability ("anyone should have seen it" applied to genuinely uncertain ex-ante info?). Countermeasures: memory → pull records; inevitability → list 3-5 alternative outcomes; foreseeability → identify what pre-outcome info would have made it predictable.
When to use it
- someone says 'I knew it all along' or 'we should have seen it coming'
- a post-mortem is blaming someone for not predicting an outcome
- a team is reviewing a past decision and the outcome is coloring the judgment
- a decision-maker is being evaluated on what happened rather than what was knowable at the time
When not to use it
When the decision is routine and reversible, applying a formal method costs more than it returns.
Worked example
"The AI Boom Was Obviously Coming" — Retrospective Inevitability in the ChatGPT/Nvidia Era (2022–2026)
Fischhoff's lab work and the Caplan-Posner-Cheney medical study both isolated hindsight bias in controlled settings. The 2022–2026 AI boom is the same distortion playing out at civilizational scale and in real time: after ChatGPT's launch and Nvidia's run, a dominant narrative emerged that the generative-AI wave and the compute buildout were "obviously coming" — a claim that, if believed, corrupts how investors, operators, and policymakers calibrate the next set of bets.
Install this skill (free, MIT)
npx skills add deciqAI/knowledge-skillsUseful? Star the repo — stars help other builders find it.
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