Hua shanshui xu 畫山水序 is China's oldest treatise on landscape painting. It was written during the Liu-Song period 劉宋 (420-479) by Zong Bing 宗炳 (375-443), courtesy name Shaowen 少文, from Nieyang 涅陽 in the commandery of Nanyang 南陽 (today's Zhenping 鎮平, Henan). He was befriended with the monk Huiyuan 慧遠 (334-416), with whom he founded the White Lotus Society (Bailian She 白蓮社) on Mt. Lushan 廬山. Paintings of him were still existing during the early Tang period 唐 (618-907). He also wrote the books Hengshan Lushan ji 衡山廬山記 and Mingfolun 明佛論.
Because Zong was an adherent of Buddhism, his painting theory is influenced by some Buddhist concepts, but also by Daoist thinking. The shape (xing 形) of individual parts of the landscape was symbolizing the inherent "Way" (dao 道) of nature, like an image of the beauty of the Way (yi xing mei dao 以形媚道), or in Buddhist words, an expression of the vanity of the world. While painting, the artist should have the potency to thoroughly penetrate the spirit (chang shen 暢神) and the soul (ling 靈) of the object and its beauty, namely in reflecting shape by depicting shape, and colour by configuring colour. In order to realize this, the painter had to see to it that the objects his eyes were seeing found a focus in his heart (ying mu hui xin 應目會心), and that that these concentrated aspects were a reflection of the spirit of the world (ying hui gan shen 應會感神). Painting was thus a process of "spiritual thinking" (shen si 神思) achieved after purifying one's mind (cheng huai 澄懷). It was not an copy of the real landscape, but an idealisation of it or rather of what was believed to be spiritually inherent.
In the practical field, Zong gave advice to paint distant objects smaller than closer ones.
The text was written about 430 CE and is found in the series Jindai mishu 津逮秘書, Wangshi shuhua yuan 王氏書畫苑, Shuhuapu 書畫譜 and Lidai minghua ji 歷代名畫記.