Growing up in the United States in the 1950s, I was used to such things as inches, feet, yards; ounces (liquid and solid), pints, pounds, etc. Then I entered my first physics class and was bowled over by the metric system.

"My God, this is so much better! Why don't we use this?" I exclaimed.

After all; remembering that a kilometer is 1,000 meters is so much easier than remember that a mile is 5,280 feet and that a foot in turn is 12 inches. Remembering that a kilogram is 1,000 grams is so much easier than remembering that a pound is 16 solid ounces. Remembering that a liter is 1,000 milliliters is so much easier than remembering that a pint is 16 fluid ounces, that two pints (32 ounces) is a quart, and four quarts (128 ounces) is a gallon.

The Celsius system also seemed much easier than the Fahrenheit system. After all, water freezes at 0° C and boils at 100° C, which appeared considerably more logical than water freezing at 32° F and boiling at 212° F.

So why did the United States, Great Britain, and a number of other countries use these weird systems?

I got the answer the moment I stepped outside of the physics classroom. Although I mathematically understood metric units, I had no feel for them. If I went into a restaurant, I knew exactly what I was getting if I ordered an 8, 10 or 12 ounce steak. But if the menu had shown a 230, 280 or 340 gram steak, I would have been completely lost. Likewise, if I had to drive 60 miles, I understood that this meant about an hour on the road. But if I had to drive 95 kilometers, I would have had no idea of what this meant -- other than it seemed to be considerably farther.

Every change is one's basic routine is difficult, even if it is clearly an improvement. So it will still be some time before Liberia, Myanmar (Burma) and the United States, the only three countries that have not yet adopted the metric system, finally make the change. But it does seem to be inevitable.

France adopted the metric system in 1799, one of the consequences of the French Revolution. Japan made it official in 1868 and Russia in 1917. Even Great Britain, which initially spread inches, feet, miles, ounces, pounds, etc., around the world, joined the club in 1965.

Now that the world has gone so massively metric (and the holdouts are likely to do so in the foreseeable future), the question is: Why not complete the job? The fact is, even metric countries still use a number of old-fashioned, non-metric units that are largely irrational and mathematically cumbersome.

For example, why is an hour 60 minutes, and a minute 60 seconds, when an hour could be 100 minutes and a minute 100 seconds? For that matter, why is a day 24 hours rather than 10 hours, each hour made up of 100 minutes and each minute made up of 100 seconds? And why stop there? Why is the year made up of 12 months rather than 10?

If you think about it, the year used to be made up of ten months until Julius Caesar (July) and Caesar Augustus (August) stuck their vanity into it. Vestiges of the old ten-month calendar can still be seen in the names of the last four months of the year: September (septum = seven), October (octo = eight), November (novum = nine), and December (decem = ten). These should have been updated centuries ago.

Another apparently bizarre unit is the 360 degrees of a circle, with each degree being divided into 60 minutes, and each minute divided into 60 seconds. Couldn't the circle be 100 degrees, divided into 100 minutes, divided into 100 seconds?

Well, yes it could.

Some mathematicians might argue that a system based on 60 has certain advantages for calculations over the metric system based on 10. For specialty applications, they could retain the 360 degree system, but there is no reason why the rest of us should suffer with it. In fact, for certain applications the 360 degree circle has been abandoned in favor of the two radian circle, based on the formula for circumference C = 2 π r (circumference = two times pi times radius)..

It is possible to cite many other measures that could be decimalized. However, we must be careful to make a distinction between conventional measures and natural ones.

It is a convention to have 60 seconds in a minute, 60 minutes in an hour, and 24 hours in a day. For whatever reason, we chose these units. However, it is not a convention that the year has 365 days because this is the time it takes the Earth to orbit the sun. This is a natural unit dictated by nature. It would make no sense to divide the year into 100 days just to make calculations easier.

Such non-sense is not beyond human ignorance. At the end of the 19th century, an American states came very close to passing a law fixing pi at an even 3 in the belief that using it at its true value (3. 3.14159265 . . .) was just too cumbersome!

When considering possible changes, we should be aware that the definitions fundamental units can change over time, often due to developments in science.

For example, since 1898 the kilogram, the basic unit of mass, has been defined in terms of the of the international prototype kilogram (IPK). This is a specifically constructed block of metal alloys maintained under minutely specified environmental conditions at the International Bureau of Weights and Measures in Sèvres, France. However, since the IPK is subject to mass drift (changes in mass over time), serious discussions are now going on to redefine the kilogram in terms of a fixed number of carbon-12 atoms, silicon atoms, or other fundamental, reproducible physical properties.

The fact is, the IPK is the only SI unit (International System of Units) still defined in terms of a carefully conserved reference model. All others have been converted to physical properties reproducible anywhere in the world. For example, the meter used to be defined by a platinum-iridium rod. However, today it is defined as 1/299,792,458 of the distance travelled by light in 1 second (the "light-meter"), the denominator of the fraction being the speed of light in a vacuum

So when will the circle, the clock, and the calendar go metric? Probably not in the near future, but for psychological reasons rather than scientific ones.

Although few people use the 360 degree circle in their daily lives, this is how they learned (and suffered through) geometry in school, so they would likely oppose changing it simply because it would be inconvenient to do so. Also, certain aspects of the 360 degree circle have become common currency in many languages, where the equivalent of an "about-face" is often described as a "180 degree turn".

Everyone uses the clock and the calendar constantly; they are integral to the fabric of daily life. Any attempt to decimalize them is almost certain to engender extremely stiff opposition. For the vast majority of people, such a change would not be just an inconvenience, but a major upheaval.

For millennia, the prospect of "squaring the circle" remained a mathematical challenge. In 1882 it was shown to be impossible because of the transcendental nature of pi. Making the circle "less round" (going from 360 degrees to 100 degrees) is not impossible, but chances are it will seem that way for a very long time to come.

Philip Yaffe is a former reporter/feature writer with The Wall Street Journal and a marketing communication consultant. He currently teaches a course in good writing and good speaking in Brussels, Belgium. His recently published book In the "I" of the Storm: the Simple Secrets of Writing & Speaking (Almost) like a Professional is available from Story Publishers in Ghent, Belgium (storypublishers.be) and Amazon (amazon.com).

For further information, contact:

Philip Yaffe
Brussels, Belgium
Tel: +32 (0)2 660 0405
phil.yaffe@yahoo.com, phil.yaffe@gmail.com