Shedaoren 赊刀人,which means people who sell knives on prophecy.They usually appears in China's villages,To sell knives,Instead charging you money right away,They tell a prophecy,Usually some food price prophecy like rice going up and down,or fruits price,Some time involving a dynasty's fall or rise,Or plague.If they came true,Shedaoren will come back,and collect the money.Their prophecy doesnt always came true,If they came true,They will come back,They only sell knives.
They claim themselves as student of Guiguzi which is allegedly teacher of Sun tzu,Shedaoren has very long history,The occupation used to be called 卜卖,which means"prophecy selling"
Shedaoren are not a distant memory or extinct,They are very much alive and real,Today,They are still selling knives at villages or towns,Somewhere.