Re: Metric system (was: Re: SPF)

[Lionel Elie Mamane <lionel@mamane.lu>]

On Tue, Jul 03, 2007 at 06:25:33PM +0200, Anders Breindahl wrote:

> Also, the metric system (and to a larger extent, the SI system) has
> an arbitrary _base_ unit (ever heard of the one-meter-bar in
> Paris?).

Incidentally, that is not the reference anymore. The meter is the
distance that light crosses in absolute vacuum in 1/299,792,458s. I
believe that the kilogram is still defined by "the mass of that lump
of metal in Sèvres (near Paris, France)".

http://en.wikipedia.org/wiki/Metre

The meter's claim to "universality" (rather than non-arbitrarity) is
that it was originally based on some fraction of the earth's
circumference. The earth, that thing common to all humanity.

I don't see why you think that the second, the ampere, the kilogram,
the candela, the mole, ... are any less arbitrary than the
meter. Maybe you meant "SI has arbitrary _base_ units, but then
everything cleanly derives from that"?

-- 
Lionel