 Although ritual propriety is purely the external adornment of the principle of heaven, it must reside in human desires for it to be seen. That being the case, in the final analysis, there cannot be a heaven that is separate from humanity, or principle separate from desires…. Hence in sounds, colors, smells, and flavors, one can clearly see the communal desires (gongyu) of all beings and their communal principle (gongli). (Wang QSYS: 8:10b-11a) 