10 · Seeing
Processing Fluency
The easier something is to read and take in, the more people like it, and the more likely they are to believe it.
Evidence: Holds upWhat we do with it
- 01
Use plain words. Long words don't make a writer seem smarter; in Daniel Oppenheimer's tests they did the opposite.
- 02
Readable type and strong contrast make the same claim seem truer. That's a reason to get them right, and a reason to be careful what you make easy to believe.
- 03
Repetition feels fluent too, so a false claim can start to feel true. Check claims before you repeat them.
Examples
Getting it wrong, getting it right.
Don't
“Leverage our end-to-end solutions to optimize customer outcomes.”
Do
“We find what's slowing your customers down, and fix it.”
The evidence
What the research says.
Strong and widely repeated. Rolf Reber and Norbert Schwarz showed in 1999 that the same statement was judged true more often when it was printed in an easy-to-read color. Daniel Oppenheimer found in 2006 that needlessly complex words made writers seem less intelligent. Repetition works the same way: Alice Dechêne and colleagues pooled 51 studies in 2010 and found that hearing a statement again makes it seem truer.
Sources
- Reber, R., & Schwarz, N. (1999). Effects of perceptual fluency on judgments of truth. Consciousness and Cognition, 8(3).
- Reber, R., Schwarz, N., & Winkielman, P. (2004). Processing fluency and aesthetic pleasure: Is beauty in the perceiver's processing experience? Personality and Social Psychology Review, 8(4).
- Oppenheimer, D. M. (2006). Consequences of erudite vernacular utilized irrespective of necessity: Problems with using long words needlessly. Applied Cognitive Psychology, 20(2).
- Dechêne, A., Stahl, C., Hansen, J., & Wänke, M. (2010). The truth about the truth: A meta-analytic review of the truth effect. Personality and Social Psychology Review, 14(2).
Last reviewed November 7, 2026. How we keep this current