My research program for much of my career has been about nature-harnessing — the idea that many of the things we think of as distinctively human weren’t engineered by our genes. They were engineered by cultural evolution to fit the ancient ape brain we already had.

Speech is built from sounds resembling the fundamental physical events of solid objects interacting in the world. Writing evolved letters and visual forms that look like the kinds of contours and junctions found among opaque objects strewn about natural scenes. Music is structured to sound like the movements and expressive behaviors of another human being.

These are not arbitrary conventions laid on top of a generic brain. They are extraordinarily sophisticated culturally evolved technologies, shaped over generations to exploit the perceptual and cognitive instincts nature had already given us.

And their power is difficult to overstate. They literally helped transform us from ape to man — from Human 1.0 to Human 2.0.

Indeed, what we take ourselves to be is so thoroughly entangled with these technologies that we barely identify with the creature underneath them. Strip away language, writing, music, art, and the rest of accumulated culture, and what remains is a clever ape — but not remotely the creature we recognize as ourselves.

This is part of what I call Zoocentrism: to understand humans, start by remembering that underneath all this cultural machinery we are animals, equipped with ancient animal instincts. The great trick of civilization has been to build technologies that fit those instincts so well that they come to feel natural.

Which brings me, strangely enough, to units of measurement.

Our traditional systems of measurement were not dreamed up at a committee meeting. They culturally evolved over millennia. And, like language, writing, and music, they are positively reeking with design — accumulated solutions shaped around human bodies, human perception, human action, and the quantities that actually matter at human scales.

Metric, by comparison, is a base-10 ladder.

That’s basically it.

It has one enormous virtue: unit conversion is easy. And if you sat someone down on the first day of civilization and told them that easy conversion was the only design objective, they could invent essentially the same thing before lunch. Powers of ten. Move the decimal point. Done.

That simplicity is often mistaken for superior design.

But culturally evolved technologies tend not to be simple, because humans aren’t simple. They accumulate strange-looking structure precisely because they have been adapting to us — our bodies, our senses, our actions, our environments, our needs.

Traditional units deserve to be looked at through that lens.

The point of what follows isn’t merely to defend feet, inches, miles, pounds, cups, or degrees Fahrenheit because they’re familiar. It’s to show that beneath their apparent messiness lies something much more interesting: deep human-scale design.

We inherited these constructs after thousands of years of cultural evolution. Before throwing them away in admiration of a base-10 conversion chart, we might first ask what all that accumulated structure was for.

Imperial Units are Another Example of How…