Which Head?

Readers may recall the discussion of applied ontology that went on several years ago in Phil on Hol. In the midst of our scoffing, someone explained to us that, yes indeed, some philosophers were actually making a decent living using their degrees outside of academia, by working for a company that was trying to figure out how to move computers along the artificial intelligence road. As one person simplified the matter, it amounted to figuring out what sorts of questions computers needed to know to ask--or not to ask. For instance, a computer that was doing diagnostic work would need to "know" that, if a patient said "My head aches," the proper next question was not "which head?" Humans, the computer needs to know, have only one head.

As I reflected on this, I received a temporary bump in my self esteem, as I thought about all the things I knew--all the things I'd heretofore taken for granted as given, but that now I could put on the "knowledge" side of my balance sheet. I know that most humans have one head and two arms and legs, for instance. Admittedly, the shine wore off quickly, when I realized that it's not as if this knowledge gave me any particular leg up over other human beings, since even very young children don't seem to make mistakes about the number of heads their parents have. (Though even at a young age they may already be able to make jokes about the matter.)

But lately I've been buoyed up by a variation on this observation--buoyed up almost literally, as it turns out. Yesterday, we took a swim down at the town park about an hour before high tide. As we were drying off after our swim, we noticed two little girls in the water, lying on their stomachs. "Are they on a rock?" Peg asked. "No," I said in jest, "they're just lying on the water," and we laughed. And suddenly I realized; here's another example of that sort of knowledge--an example way more elaborate than the head case. Why did both Peg and I laugh when I said "No, they're lying on the water?" Well, because it was so obvious that they had to be lying on something--but only if you knew what you were looking at! If you don't know how water supports human bodies--or if you tried to learn how it does so by looking at first graders' drawings of people floating--you wouldn't be amused by the notion that these two girls, whose bodies we re so clearly rigidly and firmly supported by something hard were simply floating on the water. Knowing what it looks like to float is a form of knowledge. Yes, I know we all have it--or we all grow into having it, such that even when we make those drawings in first grade, we have some sense that things don't look quite right. So my noticing this knowledge isn't going to enable me to fill in for Marilyn Vos Savant⁽¹⁾ when she's on vacation. But I don't really care about that anyway (her columns are always stupid); now what I'm fascinated by is collecting up incidents like this floating incident--incidents in which these sorts of beliefs are suddenly revealed, made present.

(1)"Who's she?" asked Peg in the margin of my draft. You know who she is; she's that woman with a column in the Sunday Parade magazine. She makes some outrageous claim about being the smartest woman in the world. I wonder how many heads she has.