[dguest]

I'm fine with math, but that doesn't make it less annoying.

The real advantage of metric is that you only have to do math once to calculate something. A cc is a ml is a gram. A liter is a cubic decimeter is a kg. It's just easy. A deep lake over a few square km? O(1) GT. Understanding orders of magnitude is a useful trait in a democracy.

You hit the nail on the head here though:

> My Canadian friends learned metric as: Here's a ruler, go measure some things.

Like any language, as long as you're translating you're loosing. Post signs in km and report temperature as C and everyone will understand it in less than a decade. A few years after I had a metric thermometer in my car C seemed easy.

It's not like the US failed to think of this. In the 80s they were posting signs in km. But back then there was a real economic cost to conversion for factories and machines. Now that's mostly gone, what remains is cultural resistance.

[analog31]

We have a saying in the US, "a pint's a pound, the world around." As the other post mentions, not everything has the same density, but a lot of stuff is pretty close to water.

The ironic thing is that an Imperial pint of water weighs more than a pound.

[arealaccount]

> A cc is a ml is a gram. A liter is a cubic decimeter is a kg

Okay but what about the off chance you’re measuring something other than water?

[dguest]

Estimate as water and fudge it a bit. Conveniently the fudge factor is just the specific gravity and is already tabulated as such in a lot of fields.

But it turns out that water is a pretty good bet most of the time:

- Settled snow is around 0.25

- Dried wood is around 0.5

- Soil is around 1.2

- Rock is around 2.5

Which is pretty good if you want to answer "how much does that truck / ship / mountain / lake weigh?".

Of course there are some anomalies: Tungsten is around 20, but it's not like imperial units help here, and the name literally translates to "heavy rock".