2 ms·

I went to school with a 30cm ruler in the 80s. As a result I have an instinctual sense for that length.

• mrguyorama 2mo ago
  Why shouldn't a measurement that is so natural and familiar to most people that most human societies developed an analogous version and even places without it still end up using it, be a first class citizen of that measurement system? That's what confuses me. It's a dumb confusion admittedly. It's basically an argument to "Beauty" or aesthetics or similar.
  • oblio 2mo ago
    Why do you need feet to measure anything? I've never in my life measured anything using feet. Paces, that's a different story, but those are closer to 1m, anyway.
• ncruces 2mo ago
  It's the length of an A4 sheet of paper (also, by extension, the size of many school books, backpacks and … rulers).