Talk:List of human-based units of measurement

Roman and Greek foot

I have reverted the deletion of the Roman and Greek foot and digit entries. The grounds in the edit summary were "derived units". I am not sure what this means in the context of this list. I am aware of Berriman's theory that the Greek foot had a geodetic origin and the other units followed from this. However, this is at least controversial and the proper place to discuss this theory, if considered notable, is within the individual articles. Readers are bound to expect these units to be here, and if they are not, an explanation for their exclusion from the scope. I daresay that there is no incontrovertible proof that any of the units on this list have an anthropomorphic origin as opposed to merely having an anthropormorphic name. If it can be reliably sourced that such a division actually exists, in my opinion this should be indicated in the list in some way rather than outright removal. SpinningSpark 19:11, 11 March 2012 (UTC)

I'm not sure that "yard" shouldn't go back in on the same grounds, but have left it out for now. SpinningSpark 19:22, 11 March 2012 (UTC)

The Roman digit was defined by the Romans as 1/16 of a foot, and is thus "derived" from the foot. The Romans similarly defined the foot as 1/5 of a pace. This is common knowledge. The yard has a completely different issue: that its origin is unknown. Zyxwv99 (talk) 20:47, 11 March 2012 (UTC)

Just to give you an example of my views on this, the original Roman inch was a derived unit, 1/12 of a foot. The earliest definition we have for the English inch defines it as the length of three barleycorns. However, historians of metrology are of the opinion that the actual standard was something longer. For about the last 700 yards, it was the yard. However, there was one occasion where the English inch was legally defined as the width of a thumb. Specifically, 18 Henry VI c 16 (1439) outlaws the sale of cloth by the yard and handful and legalizes the use of the yard and inch, stipulating that the extra inch could be measured as the width of a man's thumb. Just to put this into context, cloth was heavily taxed (by the yard). The extra handful in a yard-and-handful transaction was essentially a black-market transaction. As the state repeatedly cracked down, merchants switched over to the yard and inch to avoid prosecution. The law of 1439 was essentially legalizing a minor act of tax evasion (as the lesser of two evils, i.e., preferably to greater evil of the yard and handful). The use of the thumb-width here may have been a way of signifying the state was only grudgingly tolerating the practice. The point is, I didn't tamper with the inch entry here even though, for nearly its entire history, it has not been a human-based unit of measurement, just because of this one counter-example. Zyxwv99 (talk) 21:39, 11 March 2012 (UTC)