The line “The definition of insanity is doing the same thing over and over again and expecting different results” is most famously attributed to Albert Einstein, but there is no solid evidence he ever said or wrote it.

Who actually said “the definition of insanity…”?

Researchers who track quote origins have traced the wording to recovery and self‑help contexts in the early 1980s, not to Einstein or any major scientist or philosopher. In particular:

  • A 1981 Narcotics Anonymous text included a very similar line: “insanity is repeating the same mistakes and expecting different results.”
  • Around the same time, people in Al‑Anon meetings were recorded using nearly the same phrasing in talks about addiction and behavior patterns.
  • By the mid‑1980s, newspapers quoted speakers and columnists using the phrase as a catchy saying, still without linking it to Einstein.
  • Only by around 1990 did newspapers start calling it “Einstein’s definition of insanity,” which appears to be a later misattribution rather than a documented quote.

So, if you’re asking “who said the definition of insanity?” in the sense of origin, the best-supported answer is: it emerged from recovery circles (Narcotics Anonymous / Al‑Anon) in the early 1980s and was only later incorrectly credited to Einstein.

Why do people think Einstein said it?

Einstein’s name is often attached to pithy, motivational quotes because it gives them instant authority and shareability, especially on posters, social media, and in business talks. Quote scholars and reference works on Einstein specifically list this line under “misattributed,” meaning there’s no reliable source tying it to him.

In other words, the quote is real and popular, but the Einstein attribution is almost certainly a myth.

Information gathered from public forums or data available on the internet and portrayed here.