On a typical commute to campus, I catch a bus headed south—the #2 express bus. I get off on 60th street, walk a couple blocks to the psychology building (located at 5848 S. University Avenue), head up to the 3rd floor and into my office, room 309.
In other words, when I go to work—or, for that matter, just about anywhere in Chicago—I navigate a world signposted with numbers. Numbers tell me which bus to take, what street I'm on, whether I'm on the right floor, which office is mine. What's interesting is that these are not numbers in the most familiar sense. These are numbers as names, a different and—as Alice might say—curiouser beast.
The most familiar sense of number—the one adults think of first, the one children learn early on—is the cardinal sense. This is the sense involved when we say that there are four people in a family, four pancakes in a stack, four chairs around a table, and so on. The cardinal sense, in other words, is what we're using whenever we say "how many" of something there are, and there are pretty good reasons to think this is the basic, primordial use of numbers. The phenomenon of numbers as names is sometimes called the nominal sense of number. It is undoubtedly a secondary case, but—in some pockets of the world—it is nonetheless staggeringly pervasive.
As soon as we recognize the nominal sense of numbers as distinct, questions flood in. For one: When did this practice start? Perhaps not so long ago, I would speculate. In many parts of the world (including parts of the United States), there were not even street names until recently, let alone numerical addresses for individual houses. This may seem unthinkable. But the practice of using numbers as names really only becomes useful when certain conditions are in place: there are many barely distinguishable versions of a thing—buses, houses, streets, districts, and so on—that nonetheless need to distinguished on a regular basis—by postal workers, commuters, bureaucrats, and the like. And the world was simply not full of barely distinguishable things, it seems, until industrialization and the rise of modern urban infrastructure. A related question is about how the practice of using numbers as names became so widespread. Did it spring up in many places independently as soon as conditions were ripe, or did it start in one place, catch on, and quickly overspread the globe?
Notes
1. These are just the more conspicuous 'numbers as names' I encounter in everyday life. Lurking in the background are many more: zip codes, GPS coordinates, vehicle numbers, area codes, congressional districts—the list goes on.
2. Heike Wiese—in an article titled 'The co-evolution of number concepts and counting words' (2007) that fired some of the ideas in this post—distinguishes three senses of number: cardinal, ordinal, and nominal. A bit of conceptual fuzziness enters in, I think, when we try to distinguish between the ordinal and the nominal sense. The canonical ordinal sense involves using numbers to identify position in a sequence, e.g. this is my fourth pancake. Here is where the fuzziness comes in: in many cases there is some ordinal motivation for a nominal use of number, but this motivation is opaque for most of the people who use the labels. I remember, for example, being surprised to learn that home addresses in the DC Metro area encode information about the number of city blocks from the Capitol building (more info here).
3. The phenomenon of numbers as names has a dark side—very dark, in fact—in the use of numbers as labels for prisoners.
4. Another question: what sense of numbers do people encounter most frequently in everyday life? I wouldn't be surprised if—for city-dwellers, at least—the nominal sense of numbers, despite being conceptually secondary, rivals the cardinal sense in sheer frequency.
5. A reckless hypothesis: the widespread use of numbers as names may present a stumbling block for children trying to learn the (more canonical) cardinal and ordinal senses of numbers. Imagine trying to learn the word 'dog' when many things beyond dogs—buses, highways, and buildings, for example—were also sometimes labeled 'dog.' Maddening!