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Case file

Confirmation Bias

Filed under
Too Much Information

The charge

We seek, interpret, and remember information in ways that support what we already believe. Disconfirming evidence gets less attention or gets explained away.


How it operates

People prefer cognitive consistency and dislike being wrong, so they sample evidence asymmetrically. Existing beliefs guide both search and interpretation.

Logged incidents

  1. Incident 01

    A PM interviews only users who asked for the feature and concludes demand is obvious.

  2. Incident 02

    An investor reads mostly bullish threads after buying a stock and dismisses bearish analysis as noise.

  3. Incident 03

    A hiring manager notices every signal that confirms a strong first impression and overlooks warning signs.

What to watch for

Ask yourself: 'What evidence would make me change my mind, and have I looked for it as hard as confirming evidence?'

Recommended action

Use consider-the-opposite, red teaming, and actively open-minded thinking. Require at least one serious disconfirming check before committing.

Known associates

Source of record

en.wikipedia.org

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