Kluge: The Haphazard Construction of the Human Mind (Houghton Mifflin; 2008)

For better or worse, language inherited this system wholesale. You might think of a chair, for instance, as something with four legs, a back, and a horizontal surface for sitting. But as the philosopher Ludwig Wittgenstein (1889-1951) realized, few concepts are really defined with such precision. Beanbag chairs, for example, are still considered chairs, even though they have neither an articulated back nor any sort of legs.

I call my cup of water a glass even though it's made of plastic; I call my boss the chair of my department even though so far as I can tell she merely sits in one. A linguist or phylogenist uses the word tree to refer to a diagram on a page simply because it has branching structures, not because it grows, reproduces, or photosynthesizes. A head is the topside of a penny, the tail the bottom, even though the top has no more than a picture of a head, the bottom not a fiber of a wagging tail. Even the slightest fiber of connection suffices, precisely because words are governed by an inherited, ancestral logic of partial matches.*

Another idiosyncrasy of language, considerably more subtle, has to do with words like some, every, and most, known to linguists as "quantifiers" because they quantify, answering questions like "How much?" and "How many?": some water, every boy, most ideas, several movies.

The peculiar thing is that in addition to quantifiers, we have another whole system that does something similar. This second system traffics in what linguists call "generics," somewhat vague, generally accurate statements, such as Dogs have four legs or Paperbacks are cheaper than hardcovers. A perfect language might stick only to the first system, using explicit quantifiers rather than generics. An explicitly quantified sentence such as Every dog has four legs makes a nice, strong, clear statement, promising no exceptions. We know how to figure out whether it is true. Either all the dogs in the world have four legs, in which case the sentence is true, or at least one dog lacks four legs, in which case the sentence is false — end of story. Even a quantifier like some is fairly clear in its application; some has to mean more than one, and (pragmatically) ought not to mean every.

Generics are a whole different ball game, in many ways much less precise than quantifiers. It's just not clear how many dogs have to have four legs before the statement Dogs have four legs can be considered true, and how many dogs would have to exhibit three legs before we'd decide that the statement is false. As for Paperbacks are cheaper than hardcovers, most of us would accept the sentence as true as a general rule of thumb, even if we knew that lots of individual paperbacks (say, imports) are more expensive than many individual hardcovers (such as discounted bestsellers printed in large quantities). We agree with the statement Mosquitoes carry the West Nile vi

*Is that good or bad? That depends on your point of view. The logic of partial matches is what makes languages sloppy, and, for better or worse, keeps poets, stand-up comedians, and linguistic curmudgeons gainfully employed. ("Didja ever notice that a near-miss isn't a miss at all?")

rus, even if only (say) 1 percent of mosquitoes carry the virus, yet we wouldn't accept the statement Dogs have spots even if all the dalmatians in the world did.

Computer-programming languages admit no such imprecision; they have ways of representing formal quantifiers ([DO THIS THING REPEATEDLY UNTIL EVERY DATABASE RECORD HAS BEEN EXAMINED ] ) but no way of expressing generics at all. Human languages are idiosyncratic — and verging on redundant — inasmuch as they routinely exploit both systems, generics and the more formal quantifiers.