> Suppose I invented a new ruler that measured in “abstract ruler units.” To convert from “ruler units” to inches or centimeters, you’d use a separate conversio

> Suppose I invented a new ruler that measured in “abstract ruler units.” To convert from “ruler units” to inches or centimeters, you’d use a separate conversion chart. If I offered such a ruler to a carpenter, they’d smack me in the face with it. It would be absurd to add a layer of abstraction to a tool that gives clear, unambiguous information. Assuming these ARUs are linear (like every unit of measure for distance), you don't need a chart. You just need a multiplier. In that case, it sounds like this is describing a scale ruler [1] -- and your carpenter probably loves it. For anyone who ever has to read (or draw) an architectural diagram, they're great! Rather than adding a level of abstraction, they remove one. I'm glad rulers haven't simply "existed in the same form for hundreds of years". [1]: https://en.wikipedia.org/wiki/Scale_ruler https://en.wikipedia.org/wiki/Scale_ruler