Rice as money: why trading works as it does
Published
How trading plays: Trading.
Rice is the money
Why: “or we use rice as currency.” Rice is ordinary cargo, 1.3 m³ a tonne, so money takes room and wealth has to be hauled. The anchor is Edo Japan, where a koku of rice was about what one person ate in a year[1] and samurai were paid stipends in koku[2].
One price both ways, the same everywhere
Why: “it’s post-apocalypse-ish so humans shouldn’t price-gouge each other.” A town pays exactly what it charges, and every town charges the same, for now.
Lots in whole tonnes
Why: rice moves in whole tonnes, so every lot is sized to cost a whole number of tonnes (2,000 rounds to a lot, fuel in 2 m³ tanks). Anything bought and sold back comes out even.
A point defence turret costs 25 t
Why: prices hang off one scale: a Striker is worth 100 t of rice, and other things are priced against it. The turret’s 25 t comes from that scale; every other price is a placeholder.