For a handful of days I have been meaning to comment on lago’s post about aptitude and expertise. The post coincides with some interests I have had for a little while, about the workings of authority and knowledge—how the combination creates difficulties integrating non-experts with experts. But as is often the case, I appreciated the post without having much to add. So that’s that.

And then yesterday lago suggested that he had re-caulked his tub. Having owned a little old house for a couple of years now, I have become somewhat familiar with the realm of caulk and grout, in addition to developing some skill with a circular saw and a prybar. So maybe I have something to say regarding the earlier post on expertise, after all. Home repair strikes me as one field in which expertise is undoubtedly important. I did a much better job on the second room I painted than on the first; and I got a little practice with wiring by replacing the switch in a lamp before I tried to hang a new ceiling fan. All the while, I’m getting better at planning projects, measuring twice (and cutting once), and keeping my work area clean.

I can do many of these things without calling on a contractor or other professional tradesperson because places like Home Depot, Sears, and give regular folks like me the idea that we can do it ourselves. Indeed, there’s a huge market in facilitating the work of non-experts in domains like home repair. The limit on doing it myself often comes down to the costs of specialization: I can’t afford the carriage to plane the narrow end of a new door, for example, but a door shop that does it all the time makes an investment in the right machinery. To say nothing of time; I’m working on a dissertation, you know, leaving me little time (only three or four days a week, maximum) for other work. Ah.

In many situations, expertise is secondary to credential. I can’t move more than _x_ cubic yards of dirt in my yard without a city inspector’s approval; it takes a licensed plumber to hook up the gas line to a new water heater; an inspector checks out the house before the bank will approve a loan. We rely on the expertise behind the credential to assure us that these professionals know what they’re doing, and in theory the keys of professionalism (peer evaluation, training, internally standardized sets of practices, restriction of practice to experts) support our faith in them. But the professionals make plenty of mistakes; our inspector overlooked a few really important problems with our house—he caught roof damage, but not the electrical problems, for example. In the case of the wiring, it took a non-accredited, lay expert approximately one minute to walk in the door and say, “Whoa, this needs fixing.”

We don’t know what failed—The expert’s knowledge or his professionalism?—but we do have an example of a situation where the restriction certification and the gap in knowledge create a potential problem: I can’t evaluate something that’s very important to me, both now (getting the loan dependent on the house’s condition) and in the future (somebody else getting a loan). Further, my trust in the professional is damaged and I am likely to be skeptical about future inspections. (This kind of interaction, by the way, is a subject that comes up frequently when I teach medical sociology; it’s precisely the kind of lay expert challenge that, as lago mentions, Epstein deals with in Impure Science, and that patients-as-consumers enact when they question their physicians.) The role of interested but non-expert individuals among experts is an important question, whether you’re talking about a conversation between experts (my 30-second take on the disucssion to which lago points) or about wires in drywall.

Oh, and you go lago—caulk that tile! Originally, this post was going to be about trying to hang a new door yesterday, only to find out that every single doorway in this old house is somehow non-standard. Thirty-five and five-eighths of an inch wide? What?