《后汉书·列传·荀韩钟陈列传》
因此，把晦明寒暑之气，尊卑侈约之礼作为大节，不得违反。《易》说： 天地节而四时成。 
尊卑奢俭，所以为礼：故以晦明寒暑之气，尊卑侈约之礼为其节也。
Therefore, treat the obscure and bright, cold and hot qi, the etiquette of respect, humility, extravagance, and frugality as major etiquette, which cannot be violated. The Book of Changes says: Heaven and earth are intersected, and the four seasons are formed. 