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Case file

Illusory Truth Effect

Filed under
Too Much Information
Also recorded as
Illusion of truth effect

The charge

Repeated statements start to feel true simply because they feel familiar. Familiarity gets misread as accuracy.


How it operates

Repeated exposure increases processing fluency, and the brain treats easy-to-process claims as more believable. This happens even when the repetition comes without new evidence.

Logged incidents

  1. Incident 01

    A roadmap myth becomes accepted inside a company because the same slide deck has been reused for months.

  2. Incident 02

    Customers begin to believe a weak marketing claim because they have seen it in ads, onboarding copy, and sales calls.

  3. Incident 03

    An executive keeps repeating that enterprise users do not self-serve, and the team starts treating it as fact without checking funnel data.

What to watch for

Ask yourself: 'Does this claim feel true because I have verified it, or because I have heard it many times?'

Recommended action

Use accuracy prompts and source verification before repeating or acting on a claim. A truth sandwich and prebunking can also reduce the effect in misinformation settings.

Known associates

Source of record

en.wikipedia.org

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