Generalizing From One Example

Re­lated to: The Psy­cholog­i­cal Unity of Hu­mankind, In­stru­men­tal vs. Epistemic: A Bardic Per­spec­tive

Every­one gen­er­al­izes from one ex­am­ple. At least, I do.”

-- Vlad Tal­tos (Is­sola, Steven Brust)

My old pro­fes­sor, David Ber­man, liked to talk about what he called the “typ­i­cal mind fal­lacy”, which he illus­trated through the fol­low­ing ex­am­ple:

There was a de­bate, in the late 1800s, about whether “imag­i­na­tion” was sim­ply a turn of phrase or a real phe­nomenon. That is, can peo­ple ac­tu­ally cre­ate images in their minds which they see vividly, or do they sim­ply say “I saw it in my mind” as a metaphor for con­sid­er­ing what it looked like?

Upon hear­ing this, my re­sponse was “How the stars was this ac­tu­ally a real de­bate? Of course we have men­tal imagery. Any­one who doesn’t think we have men­tal imagery is ei­ther such a fa­nat­i­cal Be­hav­iorist that she doubts the ev­i­dence of her own senses, or sim­ply in­sane.” Un­for­tu­nately, the pro­fes­sor was able to pa­rade a long list of fa­mous peo­ple who de­nied men­tal imagery, in­clud­ing some lead­ing sci­en­tists of the era. And this was all be­fore Be­hav­iorism even ex­isted.

The de­bate was re­solved by Fran­cis Gal­ton, a fas­ci­nat­ing man who among other achieve­ments in­vented eu­gen­ics, the “wis­dom of crowds”, and stan­dard de­vi­a­tion. Gal­ton gave peo­ple some very de­tailed sur­veys, and found that some peo­ple did have men­tal imagery and oth­ers didn’t. The ones who did had sim­ply as­sumed ev­ery­one did, and the ones who didn’t had sim­ply as­sumed ev­ery­one didn’t, to the point of com­ing up with ab­surd jus­tifi­ca­tions for why they were ly­ing or mi­s­un­der­stand­ing the ques­tion. There was a wide spec­trum of imag­ing abil­ity, from about five per­cent of peo­ple with perfect ei­de­tic imagery1 to three per­cent of peo­ple com­pletely un­able to form men­tal images2.

Dr. Ber­man dubbed this the Typ­i­cal Mind Fal­lacy: the hu­man ten­dency to be­lieve that one’s own men­tal struc­ture can be gen­er­al­ized to ap­ply to ev­ery­one else’s.

He kind of took this idea and ran with it. He in­ter­preted cer­tain pas­sages in Ge­orge Berkeley’s bi­og­ra­phy to mean that Berkeley was an ei­de­tic imager, and that this was why the idea of the uni­verse as sense-per­cep­tion held such in­ter­est to him. He also sug­gested that ex­pe­rience of con­scious­ness and qualia were as vari­able as imag­ing, and that philoso­phers who deny their ex­is­tence (Ryle? Den­nett? Be­hav­iorists?) were sim­ply peo­ple whose mind lacked the abil­ity to eas­ily ex­pe­rience qualia. In gen­eral, he be­lieved philos­o­phy of mind was lit­tered with ex­am­ples of philoso­phers tak­ing their own men­tal ex­pe­riences and build­ing the­o­ries on them, and other philoso­phers with differ­ent men­tal ex­pe­riences cri­tiquing them and won­der­ing why they dis­agreed.

The for­mal typ­i­cal mind fal­lacy is about se­ri­ous mat­ters of men­tal struc­ture. But I’ve also run into some­thing similar with some­thing more like the psy­che than the mind: a ten­dency to gen­er­al­ize from our per­son­al­ities and be­hav­iors.

For ex­am­ple, I’m about as in­tro­verted a per­son as you’re ever likely to meet—any­one more in­tro­verted than I am doesn’t com­mu­ni­cate with any­one. All through el­e­men­tary and mid­dle school, I sus­pected that the other chil­dren were out to get me. They kept on grab­bing me when I was busy with some­thing and try­ing to drag me off to do some rough ac­tivity with them and their friends. When I protested, they counter-protested and told me I re­ally needed to stop what­ever I was do­ing and come join them. I figured they were bul­lies who were try­ing to an­noy me, and found ways to hide from them and scare them off.

Even­tu­ally I re­al­ized that it was a dou­ble mi­s­un­der­stand­ing. They figured I must be like them, and the only thing keep­ing me from play­ing their fun games was that I was too shy. I figured they must be like me, and that the only rea­son they would in­ter­rupt a per­son who was ob­vi­ously busy read­ing was that they wanted to an­noy him.

Like­wise: I can’t deal with noise. If some­one’s be­ing loud, I can’t sleep, I can’t study, I can’t con­cen­trate, I can’t do any­thing ex­cept bang my head against the wall and hope they stop. I once had a noisy house­mate. When­ever I asked her to keep it down, she told me I was be­ing over­sen­si­tive and should just mel­low out. I can’t claim to­tal vic­tory here, be­cause she was very neat and kept yel­ling at me for leav­ing things out of place, and I told her she needed to just mel­low out and you couldn’t even tell that there was dust on that dresser any­way. It didn’t oc­cur to me then that neat­ness to her might be as nec­es­sary and un­com­pro­mis­able as quiet was to me, and that this was an ac­tual fea­ture of how our minds pro­cessed in­for­ma­tion rather than just some weird quirk on her part.

“Just some weird quirk on her part” and “just be­ing over­sen­si­tive” are rep­re­sen­ta­tive of the prob­lem with the typ­i­cal psy­che fal­lacy, which is that it’s in­visi­ble. We tend to ne­glect the role of differ­ently-built minds in dis­agree­ments, and at­tribute the prob­lems to the other side be­ing de­liber­ately per­verse or con­fused. I hap­pen to know that loud noise se­ri­ously pains and de­bil­i­tates me, but when I say this to other peo­ple they think I’m just ex­press­ing some weird per­sonal prefer­ence for quiet. Think about all those poor non-imagers who thought ev­ery­one else was just tak­ing a metaphor about see­ing men­tal images way too far and re­fus­ing to give it up.

And the rea­son I’m post­ing this here is be­cause it’s ra­tio­nal­ity that helps us deal with these prob­lems.

There’s some ev­i­dence that the usual method of in­ter­act­ing with peo­ple in­volves some­thing sorta like em­u­lat­ing them within our own brain. We think about how we would re­act, ad­just for the other per­son’s differ­ences, and then as­sume the other per­son would re­act that way. This method of in­ter­ac­tion is very tempt­ing, and it always feels like it ought to work.

But when statis­tics tell you that the method that would work on you doesn’t work on any­one else, then con­tin­u­ing to fol­low that gut feel­ing is a Typ­i­cal Psy­che Fal­lacy. You’ve got to be a good ra­tio­nal­ist, re­ject your gut feel­ing, and fol­low the data.

I only re­ally dis­cov­ered this in my last job as a school teacher. There’s a lot of data on teach­ing meth­ods that stu­dents en­joy and learn from. I had some of these meth­­flicted...on me dur­ing my school days, and I had no in­ten­tion of abus­ing my own stu­dents in the same way. And when I tried the sorts of re­ally cre­ative stuff I would have loved as a stu­ fell com­pletely flat. What ended up work­ing? Some­thing pretty close to the teach­ing meth­ods I’d hated as a kid. Oh. Well. Now I know why peo­ple use them so much. And here I’d gone through life think­ing my teach­ers were just in­ex­pli­ca­bly bad at what they did, never figur­ing out that I was just the odd out­lier who couldn’t be reached by this sort of stuff.

The other rea­son I’m post­ing this here is be­cause I think it re­lates to some of the dis­cus­sions of se­duc­tion that are go­ing on in MBlume’s Bardic thread. There are a lot of not-par­tic­u­larly-com­pli­men­tary things about women that many men tend to be­lieve. Some guys say that women will never have ro­man­tic re­la­tion­ships with their ac­tu­ally-de­cent-peo­ple male friends be­cause they pre­fer alpha-male jerks who treat them poorly. Other guys say women want to be lied to and tricked. I could go on, but I think most of them are cov­ered in that thread any­way.

The re­sponse I hear from most of the women I know is that this is com­plete balder­dash and women aren’t like that at all. So what’s go­ing on?

Well, I’m afraid I kind of trust the se­duc­tion peo­ple. They’ve put a lot of work into their “art” and at least ac­cord­ing to their self-re­port are pretty suc­cess­ful. And un­happy ro­man­ti­cally frus­trated nice guys ev­ery­where can’t be com­pletely wrong.

My the­ory is that the women in this case are com­mit­ting a Typ­i­cal Psy­che Fal­lacy. The women I ask about this are not even re­motely close to be­ing a rep­re­sen­ta­tive sam­ple of all women. They’re the kind of women whom a shy and some­what geeky guy knows and talks about psy­chol­ogy with. Like­wise, the type of women who pub­lish strong opinions about this on the In­ter­net aren’t close to a rep­re­sen­ta­tive sam­ple. They’re well-ed­u­cated women who have strong opinions about gen­der is­sues and post about them on blogs.

And lest I sound chau­vinis­tic, the same is cer­tainly true of men. I hear a lot of bad things said about men (es­pe­cially with refer­ence to what they want ro­man­ti­cally) that I wouldn’t dream of ap­ply­ing to my­self, my close friends, or to any man I know. But they’re so com­mon and so well-sup­ported that I have ex­cel­lent rea­son to be­lieve they’re true.

This post has grad­u­ally been get­ting less rigor­ous and less con­nected to the for­mal Typ­i­cal Mind Fal­lacy. First I changed it to a Typ­i­cal Psy­che Fal­lacy so I could talk about things that were more psy­cholog­i­cal and so­cial than men­tal. And now it’s ex­pand­ing to cover the re­lated fal­lacy of be­liev­ing your own so­cial cir­cle is at least a lit­tle rep­re­sen­ta­tive of so­ciety at large, which it very rarely is3.

It was origi­nally ti­tled “The Typ­i­cal Mind Fal­lacy”, but I’m tak­ing a hint fromt the quote and chang­ing it to “Gen­er­al­iz­ing From One Ex­am­ple”, be­cause that seems to be the link be­tween all of these er­rors. We only have di­rect first-per­son knowl­edge one one mind, one psy­che, and one so­cial cir­cle, and we find it tempt­ing to treat it as typ­i­cal even in the face of con­trary ev­i­dence.

This, I think, is es­pe­cially im­por­tant for the sort of peo­ple who en­joy Less Wrong, who as far as I can tell are with few ex­cep­tions the sort of peo­ple who are ex­treme out­liers on ev­ery psy­cho­me­t­ric test ever in­vented.


1. Eide­tic imagery, vaguely re­lated to the idea of a “pho­to­graphic mem­ory”, is the abil­ity to vi­su­al­ize some­thing and have it be ex­actly as clear, vivid and ob­vi­ous as ac­tu­ally see­ing it. My pro­fes­sor’s ex­am­ple (which Michael Howard some­how re­mem­bers even though I only men­tioned it once a few years ago) is that al­though many peo­ple can imag­ine a pic­ture of a tiger, only an ei­de­tic imager would be able to count the num­ber of stripes.

2. Ac­cord­ing to Gal­ton, peo­ple in­ca­pable of form­ing images were over­rep­re­sented in math and sci­ence. I’ve since heard that this idea has been challenged, but I can’t ac­cess the study.

3. The ex­am­ple that re­ally drove this home to me: what per­cent of high school stu­dents do you think cheat on tests? What per­cent have shoplifted? Some­one did a sur­vey on this re­cently and found that the an­swer was nobhg gjb gu­veqf unir purn­grq naq nobhg bar gu­veq unir fub­cyvs­grq (rot13ed so you have to ac­tu­ally take a guess first). This shocked me and ev­ery­one I knew, be­cause we didn’t cheat or steal dur­ing high school and we didn’t know any­one who did. I spent an af­ter­noon try­ing to find some proof that the study was wrong or un­rep­re­sen­ta­tive and com­ing up with noth­ing.