The basis for the meter was intended to be a sub-division of the circumference of the Earth, but turned out to be off significantly. But the whole criterion for unit selection was inappropriate, imo. I think the concern should have been to best adapt the unit to human needs. But perhaps this should have been the subject for a Christmas Diary on Feet and Mouths. As the Dutch said while fighting the Spanish: "It is not necessary to have hope in order to persevere."
Well, the metre and the yard are within 10% of each other. Why is is the foot better adapted to human measurements than the yard? Why should people be 6 feet tall rather than two yards tall?
Then, you're picking the centimetre and the metre which are a factor of 100 apart, compared to the inch and the foot which are a factor of 12 apart. You forget the decimetre (10cm) which is about halfway between the inch and the foot (one decimetre = 4 inches, one foot = 3 decimetres) just like the foot is halfway between the decimetre and the metre (almost exactly halfway between the decimetre and the yard).
The centimetre is like the half-inch. I don't see why one unit should be better than the other in an absolute sense. This is all a bunch of rationalisations for preferences based on familiarity.
The basis for the meter was intended to be a sub-division of the circumference of the Earth, but turned out to be off significantly.
Huh? The metre is not significantly off the 10-millionth part of the distance from pole to equator (it's off only by about 0.02% !!) and the order of magnitude has been known since Eratosthenes in the 2rd century BC to within a few percent. En un viejo país ineficiente, algo así como España entre dos guerras civiles, poseer una casa y poca hacienda y memoria ninguna. -- Gil de Biedma
ARGeezer:
I think having a decimal system with the foot as the standard unit of length, the inch as a tenth of a foot, a ten-foot, hundred-foot, thousand-foot and ten-thousand foot measure would be handier.
So you're arguing that imperial measures are less suited to human use (other than the foot)? Any idiot can face a crisis - it's day to day living that wears you out.
My preferences don't matter in the scheme of things and I, of course, have no idea what my preferences would be had I grown up using the metric system. But the USA is still largely on traditional measures, for better or worse. I carry some conversions in my head. 1m = 39.37". 1" = 2.54 cm. 10cm ~ 4". 1km = .62 miles. But I have never had the opportunity to obtain customary familiarity with "native" use of metric measures of length. Yet for small volumes ccs are more intuitive to me than teaspoons or tablespoons, etc.
The metrics I live with are truly bastardized. As the Dutch said while fighting the Spanish: "It is not necessary to have hope in order to persevere."
