22 Juni 2006

The Metric System

The other day I engaged in a conversation--well, to be honest, a recitation--that I have repeated more often than I can remember. It began when I lived in Germany several years ago. As an American, I quickly discovered that when talking to me most people tended to gravitate towards a select number of subjects, one of which invariably had to do with the old-fashioned Anglo-American system of weights and measurements. Why, ask the rationalistic, Cartesian-influenced Europeans, don't we Americans, in most respects purportedly so high-tech, bite the bullet and make the switch? The short answer, of course, is that as a superpower we don't have to; we are the 800-pound gorilla that gets fed whatever it wants (though nowadays the other gorillas are rapidly getting bigger too, while our gorilla is getting long in the tooth, but that's another tale).

To that extent, our critics have a valid point. However, what annoys me no end is the snide comment that usually follows--that the English system is "stupid" and "makes no sense" because it is so irregular, e.g., a mile comes to 5,280 feet, 16 inches equal one pound, 14 pounds equal one stone, and so on. In fact, the system is not at all stupid; moreover, it makes more sense than the metric system, albeit for its original users: people of ordinary intelligence who are both illiterate and innumerate, to wit, the English peasantry of the Middle Ages.

Suppose that you cannot read, write or cipher--meaning that you can neither recognize arabic numbers (1,2,3), nor manipulate them on paper to come up with 2 + 2 = 4. Yet you are possessed of a normal everyday vocabulary and intelligence. The metric system, had it existed (it did not come about, fittingly enough, until the rationalistic Enlightenment period centuries later) would have been beyond your ability: you would have to be able to understand decimals, base-ten, and the concept of zero. By contrast, intuitively you would be able to understand what half, a third, a quarter, a sixth, and an eighth of something are. Now notice how inches and feet work: 12 inches comprise one foot. The number 12 is evenly divisible by 2, 3, 4, and 6--a total of four possibilities. In other words, 12 allows users to make "intuitive" or innumerate divisions without having to cipher. That's why 36 inches--not 35 or 33 or 40--equal one yard: 36 can be divided evenly by 2, 3 (making 3 feet), 4, 6, and 9!

The metric system makes higher mathematical calculations easier, because it does away with fractions. We found fractions difficult in grade-school math because they pre-date higher mathematics, which is rather ill-equipped to deal with them. If you are going to start multiplying and dividing, obviously decimals make more sense than fractions. But if you are just dividing something up among friends or associates--e.g., you take a third of the bushel, I'll take two thirds, each of you two gets one sixth apiece--then fractions are a lot less complicated. The same principle holds true with other English units of measure, too. One pound equals 16 ounces--16 can be divided evenly by 2, 4, and 8. If you try any of these commonplace divisions in the metric system, you end up with a recurring decimal, e.g., 3.3333~. Based as they are in units of 10, metric measurements can be divided evenly only by 2 and 5--two possibilities. When you've got calculators and the use of zero, as stated, that becomes much easier.

But, you retort, surely we don't live in that quaint medaeval world anymore, so why should we retain the old system? No reason--just the sheer weight of nearly 300,000,000 people's intransigence and inertia. Besides, Americans aren't as unfamilar with the metric system as most foreigners imagine. It's widely used by scientists and engineers. Sodas come in 2-liter bottles. Rifle and handgun ammunition are often (not always) metric: 9mm, 7.62mm, 5.55 mm. Photographers have long spoken of 35mm film and 50mm or 100mm lenses (only on very, very old cameras will you find lenses calibrated in inches). Our injections are in metric (50cc's, etc). Mechanics use metric wrenches on cars all the time. It's just that we don't want to use metric for everyday life: Americans don't want to re-learn their height, weight, commuting distance, etc., in metric. For those of you dreaming about a metric future, I suggest you try to persuade Jimmy Carter to run for President again. Having been a nuclear engineer before entering either peanut farming or politics, he tried to phase out the old system with a plan called "Metric 2000"--the U.S. was supposed to switch over by then. I can recall textbooks in my K-8 school gradually inserting metric measurements in parentheses. It all ended in 1981, when Reagan ended the program by Executive Order. Consensus among scientists and others interested in this matter holds that the chances of America adopting metrics wholesale are slim at best, and virtually nil so long as a Republican administration occupies the White House.