This was because, in Confucian feudal society, it was thought that deal accompanied by interest was vulgar, that it should had been based on the mutual trust, and that it was an issue basically to be settled inside.
これは儒教的な封建社会において金利を伴う取引が卑しまれた事に加え、こうした取引は相互信頼に基づくものであり本来は内部で解決されるべき問題であると考えられたからである。