The definition of insanity

I’ve heard from several sources that the “official” definition of insanity is something like: “repeating a process over and over again even though nothing has changed.” I’ve checked a couple dictionaries and none list anything close to that as a definition of insanity. What’s the straight dope on this?

It’s certainly not the legal definition of insanity, so you won’t find it in a dictionary. It’s just a pithy saying that’s getting a lot of play lately (yesterday’s Dilbert, for example). You’re missing a key part of the definition: repeating the same thing over and over, and expecting a different result.

I did a google on the phrase, and the closest to a source I could find was “motivational speakers”.

What I’ve heard is “The definition of insanity is repeating the same thing over and over and expecting a different result.” It’s more of a pithy saying than an actual definition of insanity.

There’s a habit of ‘the definition of’ jokes (for example - the definition of cruel - walking past an orphanage singing ‘where’s your momma gone’). This sounds like one of them.

FWIW, I most frequently hear this attributed to Thomas Jefferson, although the other day I overheard someone attributing it to Einstein.

I’ve always heard it as “one definition of insanity is…”, not “the definition of insanity is…”

And I’ve most heard it used in the context of chemical dependency.

Insanity isn’t a medical term, it’s a legal term. Insanity refers either to a mental condition that would either render one unfit to contract or that would serve to relieve the person so afflicted of culpability for criminal conduct. How insanity is defined is thus dependant on the laws of the jurisdiction, and whether any one person is insane or not is a question for a judge or jury. You can have a mental illness, even a severe one, and not be insane according to the laws of the jurisdiction, as was the case with Andrea Yates.

Yep. Take a look at the current Diagnostic and Statistical Manual (DSM), the American Psychiatric Association’s handbook of mental disorders, and you won’t find “insanity”. Rather, you’ll find a list of specific psychological disorders, whose symptoms may or may not reflect the clichéd symptoms of “insanity” you see so often in movies and on TV.

Insanity’s a legal term and definitely a Hollywood term, but not a clinical psychology or psychiatric term.

While I agree that “insanity” has a specific legal definition (or actually several, depending on context and jurisdiction) and no specific medical definition, it’s also a lay term with a broader definition than the legal one. The quip in question seems like it gets at the heart of the matter, although it isn’t really a definition, but rather an example.


I thought that was the definition of gambling. :slight_smile:

Repeating the same thing over and over, and expecting a different result.

Repeating the same thing over and over, and expecting a different result.

Repeating the same thing over and over, and expecting a different result.

Damn, it’s the same result each time.

Yeah that’s silly.


I don’t know. I think they took it with them.

Is it something to do with repeating the same thing over and over again?

Yeah, but, what if you suddenly get a different resultHooha!

But, maybe if you tried once more.

Erm, didn’t you know that everyone is insane?

Sanity is a form of conformism - John Nash

An interesting psychological study by Rosenhan, “On Being Sane in Insane Places,” deals with the issue of insanity and such. Do some googling and you’ll be intrigued. A great study.

…So broad as to be virtually meaningless when discussing mental illness in lay terms.

So wouldnt this rule out Practicing for anything?

And wouldn’t we all go insane… by reading this post, over and over again, expecting a new reply?