Yong-le: Year 9, Month 6, Day 18
8 Jul 1411
The native-official Zi En of the Qi-chu Dian Chief's Office in Yun-nan, advised: "This office annually pays 79,800 suo (strings?) of cowries (海肥) in tribute. These are not a product of this place and we have to yearly buy these from Lin-an Prefecture. It is requested that we be allowed to pay in paper money and silver." The Ministry of Revenue held that as this levy had been set during the Hong-wu reign (1368-98), it was not possible to permit the payment in other forms. The Emperor said: "Taking what they do not have will certainly harm the people. This was a mistake by the officials. Also, they are distant yi and we should be especially sympathetic to them. How can we subject them to that former levy? It is to be removed."
Zhong-yang Yan-jiu yuan Ming Shi-lu, volume 12, page 1479