Zetetic explanation

Link post

There is a kind of ex­plan­a­tion that I think ought to be a corner­stone of good ped­agogy, and I don’t have a good word for it. My first im­pulse is to call it a his­tor­ical ex­plan­a­tion, after the ori­ginal, in­vest­ig­at­ive sense of the term “his­tory.” But in the in­terests of avoid­ing no­men­clature col­li­sion, I’m in­clined to call it “zetetic ex­plan­a­tion,” after the Greek word for seek­ing, an ex­plan­a­tion that em­beds in it­self an in­quiry into the thing.

Often in “ex­plain­ing” a thing, we simply tell people what words they ought to say about it, or how they ought to in­ter­face with it right now, or give them tech­nical lan­guage for it without any con­nec­tion to the or­din­ary means by which they nav­ig­ate their lives. We can call these sorts of ex­plan­a­tions nom­inal, func­tional, and formal.

In my high school chem­istry courses, for in­stance, there was lots of “add X to Y and get Z” plus some for­mu­las, and I learned how to ma­nip­u­late the sym­bols in the for­mu­las, but this bore no re­la­tion what­so­ever to the sorts of skills used in time-travel or Robin­son Cru­soe stor­ies. Over­all I got the sense that chem­ic­als were a sort of ma­gical thing pro­duced by a mys­ter­i­ous Scientific-In­dus­trial priest­hood in spe­cial temples called labor­at­or­ies or factor­ies, not things one might find out­doors.

It’s only in the last year that I prop­erly learned how one might get some­thing as simple as cop­per or iron, read­ing David W. Anthony’s The Horse, the Wheel, and Lan­guage and Vaclav Smil’s Still the Iron Age, both of which con­tain clear and con­crete sum­mar­ies of the pro­cess. Richard Feyn­man’s ex­plan­a­tion of tri­bo­lu­min­es­cence is a short ex­ample of a zetetic ex­plan­a­tion in chem­istry, and Paul Lock­hart’s A Mathem­atician’s La­ment bears strong sim­il­ar­it­ies in the field of pure math­em­at­ics.

I’m go­ing to work through a dif­fer­ent ex­ample here, and then dis­cuss this class of ex­plan­a­tion more gen­er­ally.

What is yeast? A worked example

Re­cently my mother noted that when, in sci­ence class, her teacher had ex­plained how bread was made, it had been a rev­el­a­tion to her. I poin­ted out that while this ex­plan­a­tion re­moved bread from the cat­egory of a pure product, to be pur­chased and con­sumed, it still placed it in the cat­egory of an in­dus­trial product re­quir­ing spe­cial­ized, stand­ard­ized in­puts such as yeast. My mother ob­served that she didn’t really know what yeast was, and I found my­self ex­plain­ing.

Seeds, en­ergy stor­age, and coevolution

Many plants store en­ergy in chem­ic­als such as pro­teins and car­bo­hydrates around their seeds, to help them start grow­ing once they’re in wet ground. Some an­im­als seek out the seeds with the most ex­tra en­ergy, and poop the oc­ca­sional seed else­where. So­me­times this helps the plant re­pro­duce more than it oth­er­wise would have; in such cases, the plant may co­e­volve with the an­im­als that eat it, of­ten in­vest­ing much lar­ger amounts of en­ergy in or around the seed, since the most cal­or­ific seeds get eaten most eagerly.

Hu­mans co­e­volved with a sort of grass. If you’ve seen wild grass, you may have ob­served stalks with seed pods on them, that look sort of like tiny heads of wheat. Grain is ba­sic­ally massively a grass that co­e­volved with us to pro­duce plump, overnour­ished seeds.

En­ergy extraction

Of course, there’s only so much we can do to se­lect for di­gest­ib­il­ity. Often even plants that store a lot of sur­plus en­ergy need fur­ther treat­ment be­fore they’re easy to di­gest. Some spe­cies evolved to spe­cial­ize in di­gest­ing a cer­tain sort of plant mat­ter ef­fi­ciently; for in­stance, ru­min­ants such as cattle and sheep have mul­tiple stom­achs to break down the free en­ergy in plant mat­ter. Hu­mans, with un­spe­cial­ized om­ni­vor­ous guts, learned other ways to ex­tract en­ergy from plants.

One such way is cook­ing. If you heat up the starches in­side a ker­nel of wheat, they’ll of­ten trans­form into some­thing easier to di­gest. But bread made this way can still be dif­fi­cult to di­gest, as many eat­ers of matzah or hardtack have learned. Soak­ing or sprout­ing seeds also helps. And a third way to make grains more di­gest­ible is fer­ment­a­tion.

Cul­tured food

Where there’s dense stor­age of en­ergy, there’s of­ten leak­age. So­me­times a seed gets split open for some reason, and there’s a bit of di­gest­ible car­bo­hydrate ex­posed on the sur­face. Where there’s free en­ergy like this, mi­crobes evolve to eat it.

Some of these mi­crobes, es­pe­cially fungal ones, pro­duce byproducts that are toxic to us. But oth­ers, such as some bac­teria and yeasts, break down hard-to-di­gest parts of wheat into sub­stances that are easier for us to di­gest. Pre­sum­ably at some point, people no­ticed that if they wet some flour and left it out for a day or two be­fore cook­ing it, the res­ult­ing por­ridge or cracker was both tastier and more di­gest­ible. (Other fer­men­ted products such as sauerkraut may have been dis­covered in a sim­ilar way.)

Of course, while grain-eat­ing mi­crobes will of­ten tend to be found on grain, al­low­ing for such ac­ci­dental dis­cov­er­ies, there is no guar­an­tee that they’ll be the kind we like. Since they mostly just eat ac­ci­dental dis­charges of en­ergy, there also just aren’t very many of them, com­pared to the amount of en­ergy avail­able to them once the flour is ground up and mixed with wa­ter. It takes a while for them to eat and re­pro­duce enough to pro­cess the whole batch.

Even­tu­ally, people real­ized that if they took part of a good batch of dough or por­ridge and didn’t cook it, but in­stead ad­ded it to the next batch, this would yield an ed­ible product both more re­li­ably (be­cause the mi­crobes in the starter would have a head start re­l­at­ive to any po­ten­tially harm­ful mi­crobes) and more quickly (again, be­cause they’d be start­ing with more mi­crobes re­l­at­ive to the amount of grain they needed to pro­cess). This is what we call a sour­dough “cul­ture” or “starter”.

(You can make a sour­dough starter at home by mix­ing some flour, prefer­ably whole­meal, with wa­ter, cov­er­ing it, and adding some more flour and wa­ter each day un­til it gets bub­bly. Sup­posedly, a reg­u­larly fed starter can stay act­ive for gen­er­a­tions.)

Breads are par­tic­u­larly con­veni­ent foods for a few reas­ons. First, grains have a very high max­imum cal­oric yield per acre, al­low­ing for high pop­u­la­tion dens­ity. Se­cond, dry grains or flour can be stored for a long time without go­ing bad; as a res­ult, stock­piles can tide people over in lean sea­sons or years, and be traded over large dis­tances. Third, a loaf of bread it­self has some amount of more local port­ab­il­ity and dur­ab­il­ity, re­l­at­ive to a por­ridge.

Yeast-spe­cific products

One of the mi­crobes found in a sour­dough cul­ture, yeast, has a par­tic­u­larly simple meta­bol­ism with two main byproducts. It pisses al­co­hol, and farts car­bon di­ox­ide. Car­bon di­ox­ide is a gas that can leaven or puff up dough, which makes it nicer to eat. Al­co­hol is a psy­cho­act­ive drug, and some people likes how it makes them feel. Many food cul­tures ended up pay­ing spe­cial at­ten­tion to grain products that used one or the other of these traits: beer and leavened bread.

In the 19th cen­tury CE, people figured out how to isol­ate the yeast from the rest of the sour­dough cul­ture, which al­lowed for in­dus­trial, stand­ard­ized pro­duc­tion of beer and bread. If you know ex­actly how much yeast you’re adding to the dough, you can stand­ard­ize dough rising times and tem­per­at­ures, al­low­ing for mass pro­duc­tion on a sched­ule, re­du­cing po­ten­tially costly sur­prises.

The price of this in­nov­a­tion is two­fold. First, when us­ing stand­ard­ized yeast to bake bread, we forgo the di­gest­ive and taste be­ne­fits of the other mi­crobes you would find in a sour­dough starter. Se­cond, we be­come ali­en­ated from a cru­cial part of the pro­duc­tion of bread, to the point where many people only re­late to it as a re­cipe com­posed of products you can buy at a store, rather than some­thing made of com­pon­ents you might find out in the wild or grow self-suf­fi­ciently.

Ad­di­tional thoughts on explanation

I’m hav­ing some dif­fi­culty ar­tic­u­lat­ing ex­actly what seems dis­tinct about this sort of ex­plan­a­tion, but here’s a pre­lim­in­ary at­tempt.

Zetetic ex­plan­a­tions will tend to be in­ter­dis­cip­lin­ary, as they will of­ten cover a mix­ture of so­cial and nat­ural factors lead­ing up to the isol­a­tion of the thing be­ing ex­plained. This nat­ur­ally makes it harder to be an ex­pert in everything one is talk­ing about, and re­quires some min­imal amount of cour­age on the part of the ex­plainer, who may have to risk be­ing wrong. But they’re not merely in­ter­dis­cip­lin­ary. You could sep­ar­ately talk about the use of yeast as a lit­er­ary mo­tif, the chem­istry of the yeast cell, and the in­dus­trial use in bread, and still come nowhere close to giv­ing people any real sense of why yeast came into the world or how we found it.

Zetetic ex­plan­a­tions are em­power­ing. First, the in­teg­ra­tion of con­crete and model-based think­ing is check­able on mul­tiple levels—you can look up con­firm­ing or dis­con­firm­ing facts, and you can also val­id­ate it against your per­sonal ex­per­i­ence or sense of plaus­ib­il­ity, and val­id­ate the co­her­ence and sim­pli­city of the mod­els used. Se­cond, they af­firm the ba­sic com­pet­ence of hu­mans to ex­plore our world. By cen­ter­ing the pro­cess of dis­cov­ery rather than a fin­ished product, such ex­plan­a­tions in­vite the audi­ence to par­ti­cip­ate in this pro­cess, and per­haps to sur­prise us with new dis­cov­er­ies.

Of course, it can be hard to know where to stop in such ex­plan­a­tions, and it can also be hard to know where to start. This post could eas­ily have been twice as long. Ideally, an ex­plainer would at­tend to the re­ac­tions of their audi­ence, and try to touch base with points of shared un­der­stand­ing. Such ex­plan­a­tions also re­quire pa­tience on both sides. Another dif­fi­culty this ap­proach raises is that plain-lan­guage ex­plan­a­tions rooted in every­day con­cepts may not match the way things are re­ferred to in tech­nical or sci­entific lit­er­at­ure, al­though this prob­lem should not be hard to solve.

In some cases, one might want to for­wards-chain from an in­ter­est­ing puzzle or other thing to play with, rather than back­wards-chain­ing from a product. Lock­hart seems to fa­vor ex­plor­a­tion over ex­plan­a­tion for math­em­at­ics, and of course there’s no par­tic­u­lar reason why one can’t use both. In par­tic­u­lar, the ex­plan­a­tion paradigm seems use­ful for de­cid­ing which ex­plor­a­tions to pro­pose.

Related: The Steam­punk Aes­thetic, Truly Part Of You