[kergonath]

> Yes, but we could have decided as a civilization to count in base 12 just as we decided to measure things in the metric system

But we did not, so it’s a moot point. The metric system succeeded because it fit easily with how people measured things and had some unarguable upsides (like replacing the ~20 different units of length all called “foot”). The metric system itself was not a great step into decimalisation, it was just the recognition that the number systems in used were decimal already. That’s why it was so easily adopted.

You can see it in the units that were not accepted and then all but disappeared: the time and angle units, for which the non-decimal units had practical advantages.

[montefischer]

It took over a half-century (<=1801 to >=1858) to get France onto the metric system, Wikipedia estimates: https://en.wikipedia.org/wiki/History_of_the_metric_system. The systems it replaced were forgotten, but what cannot be doubted is that those "vernacular" systems were hyper-adapted to how ordinary people used measurements in daily life. It was the demands of state taxation and international trade, not the needs of common people, that promoted the creation and adoption of the metric system by legislative fiat.

[kergonath]

> It took over a half-century (<=1801 to >=1858) to get France onto the metric system, Wikipedia estimates

Sure, these things never happen instantly. Some units remained in the daily language, like livre, pinte, sou (respectively pound, pint, and shilling). There was no internet at that time, and France went through 3 revolutions and quite a few regime changes. It never was a priority after Napoleon, as the restored monarchs tried to leave as much of the revolution behind them. The people saw the advantages of a consistent decimal system.

> The systems it replaced were forgotten, but what cannot be doubted is that those "vernacular" systems were hyper-adapted to how ordinary people used measurements in daily life.

We can very much doubt that they were optimal, otherwise they wouldn’t have ended with hundreds of small variations of common units. They evolved in isolation at times when consistency was not very relevant at best, or a tool for price gouging at worst. You cannot have that in a modern, integrated nation state such as what France was turning into after 1789.

> It was the demands of state taxation and international trade, not the needs of common people, that promoted the creation and adoption of the metric system by legislative fiat.

That is quite far from reality. It was created as a scientific and technological toy, and the logical conclusion of some Enlightenment ideas that were brewing before the revolution.

There were some propaganda aspects when they got a bunch of funding from the Convention to do some actual measurements, and Napoleon realised how useful it could be for administrative purposes. But the metric system did not just appear one day, ready to be used by bureaucrats. It was not designed by bureaucrats either, at least before the metre convention.

The bureaucrats would have been perfectly happy with a unified system based on the old units just like in the UK.