Sunday Book-Thought 55

To make this essential point clear it helps to take an example used by Minsky and look at what is involved in understanding a piece of everyday equipment as simple as a chair. No piece of equipment makes sense by itself. The physical object which is a chair can be defined in isolation as a collection of atoms, or of wood or metal components, but such a description will not enable us to pick out chairs. What makes an object a chair is its function, and what makes possible its role as equipment for sitting it its place in a total practical context. This presupposes certain facts about human beings (fatigue, the ways the body bends), and a network of other culturally determined equipment (tables, floors, lamps), and skills (eating, writing, going to conferences, giving lectures, etc.). Chairs would not be equipment for sitting if our knees bent backwards like those of flamingos, or if we had no tables as in traditional Japan or the Australian bush. Anyone in our culture understands such things as how to sit on kitchen chairs, swivel chairs, folding chairs; and in arm chairs, rocking chairs, deck chairs, barber’s chairs, sedan chairs, dentist’s chairs, basket chairs, reclining chairs, wheel chairs, sling chairs, and beanbag chairs – as well as how to get out of them again. This ability presupposes a repertoire of bodily skills which may well be indefinitely large, since there seems to be an indefinitely large variety of chairs and of successful (graceful, comfortable, secure, posed, etc.) ways to sit in them. Moreover, understanding chairs also includes social skills such as being able to sit appropriately (sedately, demurely, naturally, casually, sloppily, provocatively, etc.) at dinners, interviews, desk jobs, lectures, auditions, concerts (intimate enough for there to be chairs rather than seats), and in waiting rooms, living rooms, bedrooms, courts, libraries, and bars (of the sort sporting chairs, not stools).
– Hubert L. Dreyfus, What Computers Still Can’t Do: A Critique of Artificial Reason (Cambridge, MA: The MIT Press, 1992; rep. 1994 [Fourth Printing]), pp. 36-37.