Rhyme-as-reason effect
Statements that rhyme seem more truthful and persuasive than ones that do not.
What it means
The rhyme-as-reason effect, or Eaton-Rosen phenomenon, is the tendency to judge rhyming aphorisms as more accurate descriptions of the world than semantically equivalent non-rhyming versions. The mechanism is processing fluency: rhyme makes a phrase easier to process and recall, and that fluency is misattributed to truth, a special case of the broader fluency-truth link. The effect shows how purely formal, aesthetic properties of a message can sway substantive judgments of credibility, with obvious implications for slogans, proverbs, and rhetoric. People discount the effect when alerted to it or asked to focus on content. It is a compact demonstration that style can masquerade as evidence.
Examples
'Woes unite foes' is rated a truer claim about the world than 'Woes unite enemies,' though the two mean the same thing.
'If it doesn't fit, you must acquit' lodged in the public memory of the O.J. Simpson trial in a way that 'you must find him not guilty' never would have.
'An apple a day keeps the doctor away' gets quoted as folk wisdom, while 'eating fruit daily keeps you healthy' says the same thing and is treated as mere opinion.
First described in McGlone & Tofighbakhsh (2000).