敦煌文書「中祥」一詞，歷來鑽研敦煌學之學者，咸以「中祥」為唐、五代敦煌地區之習俗，不見於傳統禮制與中原。然緣情制禮，時異代殊，故禮制有所變革之際，必權衡從時，有其嬗變之迹；故思於載籍考斠，甄覈董理，有足互證者，以探賾索隱「中祥」之流轉，求厥至當。「中祥」服制，因敦煌文書而為世人所重，唯不見於禮經，故多以「中祥」為唐、五代敦煌之殊制；殊不知禮制百代承傳，斟酌損益，有其相因相革之迹。自唐五代上溯東漢魏晉南朝，下逮趙宋，徵諸典籍，喪服服制之「中祥」，雖禮經不載，然行之歷代，為介於「小祥」、「大祥」之受服，不獨為敦煌地區之習俗。「中祥」不見於禮經，雖先王之所未有，可以義起也；禮有權變，變而從時，容或非古，未嘗悖離禮義，則「中祥」無乃為禮制之重要環節乎。

The term Chung Hsyoung in Dun-Huang letters was a special local custom during Tang Dynasty and Five Dynasties periods at Dun-Huang area, and was not a Chinese traditional etiquette, as argued by several Dun-Huang specialists. However, etiquettes may change with time and space. The purpose of this study was to prove that Chung Hsyoung etiquette was not only at Dun-Huang area and not only during Tang Dynasty and Five Dynasties periods. Chung Hsyoung was rarely described in classics of rites. However, other documents from East Han Dynasty and Wei Gin South Dynasty, prior to Tang Dynasty and Five Dynasties, to Soung Dynasty do mention the etiquette of Chung Hsyoung, an etiquette between Hsiao Hsyoung and Da Hsyoung, indicating that the etiquette was not only at Dun-Huang area but also at other areas of China and not only during Tang Dynasty and Five Dynasties periods but also before and after those periods.