[permaculture] Metric vs English

Eugene Monaco efmonaco at comcast.net
Mon Jun 11 16:59:38 EDT 2007

Nice post Toby.  I have often related when I heard of some native americans
using terms to measure time, like when the sun is 4 fingers high (horizontal
fingers, that's when you check your traps).  Also, my grandmother from
Sicily, when asked how long something was, measured things from the end of
her fingers to the place on her inner forearm where she put her other hand
(like a karate chop).  This long, she would gesture.  I'll remember this the
next time I'm suffering through a string of calculations on a set of drawing
that reads something like this:  23'-6-1/4" + 3'-2-1/2" + 3-7/8" + 9/16" +
12'-6-1/8" - 5/8" = What?  Quick now, without one of those handy-dandy
builder's calculators.

Gene Monaco
Knoxville, TN  
From: Toby Hemenway 

Disclaimer: As an American scientist I use both English and metric with
equal ease; I'm guilty of once saying "as soon as I get these enzymes into
the 37-degree bath I'm going outside, because it's in the 80s out there."

Rant, only vaguely related to Pc but interesting, I think:

Years ago there was a great article in Whole Earth Review entitled "The
Metric System, Pro and Con." It went like this:

Pro: You can divide things by ten.

Con: And here followed about 5 pages of cogent argument pointing out that
with calculators and computers there's little advantage to dividing by 10,
that Metric was devised by Robespierre and his Revolutionary gang
specifically because it was unlike anything that had gone before and had no
relation to anything in the real world, and that its levels of false
precision rendered it deceptive and not very useful for the daily kind of
measuring that most people do. I think for permaculturists the argument that
metric has nothing to do with human or natural history and objects is so
obvious that I need pursue it no more. We each carry around with us feet,
fathoms, hands (as in horse measurements), and the other familiar items that
give measurements some humanity, as opposed to knowing how many diameters of
a Cesium atom, or whatever, there are in a meter, as it's defined. But even
if you prefer the disembodied logic of science over a connection to the real
world, metric measurement scales very poorly and is utterly unable to give
the sense of context that English measurements do. Here's what I mean.

I'm 5 feet, 11 inches tall, or "just under six feet" as I say when I'm being
less precise. That doesn't vary more than an inch whether I'm barefoot and
slouching or standing straight in boots. But I'm rarely exactly 179 cm
tall--I have joints that move, a spine that flexes. Let's round that to 180,
because the false precision of 179 is just silly. But would a genuine 6
footer want to round his height down? No, he'd want to claim his full 183
cm. Now there's a catchy number! And you could never say either of us was
"just under 2 meters tall." Very few people are; meters don't fit people.
But we know lots of people who are about 6 feet, or about 5 feet tall. It's
a human scale. 

Scaling by a factor of ten as metric does is too coarse and crude to be of
much use in the real world. Any good architect or designer will tell you
that jumps in scale of more than 2- to 4-fold lead to ugly, mechanical
designs. And that problem of too much precision and poor scaling robs us of
context as well as utility.

Say there's an opening in a wall--eyeball it at "about 20 inches across."
That's a good scale for eyeballing. We want to put a window in it, so we get
out our tape measure and find it's "about 19 and a half inches." Now we've
changed by a factor of two, from inches to half-inches, instead of the
enormous jump of ten-fold that metric demands, and half-inches are the
perfect scale to tell is us what thickness of boards to use: 2x4s for the
frame. To cut them, we measure again, more carefully: 19-3/4 inches. We've
divided our scale by 2 again to quarter-inches, and that's the right scale
to cut the 2x4 framing for the window. Next we want to do finish carpentry
for the window trim, and choose the next 2-fold scale, eighth inches, or
maybe sixteenths if we're good enough. See how nice that 2-fold scaling is?
Each 2-fold change is perfectly in line with the degree of precision you
need. For the little trim around the window we want to be down 2-fold more,
to sixteenths or 32nds, and if we're doing fine cabinetry, another 2-fold
division to 64ths gives us the information we need. Whereas if you were
working in metric, you'd be at bizarre measurements like 2.47 cm or 24.76
mm. So how has dividing by ten helped you there? Using base 2 instead of
base 10 provides context and setting for each scale you use, and is far more
appropriate for human-scale, natural measurement. We encounter these scale
issues many times each day; metric is a pain to use for them.

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