Quote
“A reliable way to make people believe in falsehoods is frequent repetition, because familiarity is not easily distinguished from truth.”
— Daniel Kahneman, in Thinking, Fast and Slow (2011) · Thinking, Fast and Slow →
Why it was said
Daniel Kahneman writes this in 'Cognitive Ease', the fifth chapter of Thinking, Fast and Slow. The chapter describes how System 1, the fast and automatic side of the mind, reads the ease with which something is processed as a sign that it is true, safe or good.
What it actually means
The mind uses a shortcut: if a statement feels easy to process, it is probably true. Most of the time that works, because true things are often the ones we hear repeatedly. But the shortcut cannot tell hearing something often because it is true from hearing it often because someone kept saying it. Repetition produces the same feeling of familiarity either way, and familiarity feels like knowing. That is why a rumour gains credibility just by circulating, and why a slogan repeated for years starts to sound like common sense. The defence is to separate 'I have heard this a lot' from 'I have a reason to believe this'.
How to use it
- 1When a claim feels obviously true, ask where you first heard it and what evidence came with it.
- 2Before sharing a message in her family WhatsApp group, Ayşe in Antalya checks whether she believes it because of a source or because three relatives have already forwarded it.
- 3When you correct a false claim, repeat the true version rather than the myth; every repetition of the myth adds to its familiarity.