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