Services should, over time, rise in price compared to manufactured goods.
Or, to cast the same story another way, one hour of services labour should, over time, cost about the same multiple of manufacturing labour. Obviously, it’s not one hour for one hour, as some services jobs are more difficult, more distasteful, whatever, than some manufacturing jobs (and vice versa). But the ratio should stay static-ish, the increasing productivity of manufacturing hours leading to manufactures being less expensive per unit than services output.
The first exhibit in the museum has a painting on the wall of a 400-year-old Chinese trade ship in Thailand. Wooden buckets of rice sit in front of it, the payment used for sex by sailors.
“Sex work was legal back then,” Apisuk says. “Sex would cost 15 kilos of rice. That much rice costs roughly 1,050 baht [£20] today. So the price hasn’t changed.”
Not perfect but appears about right.