Wulilun 物理論

Wulilun 物理論 "On the order of things", full title Yangzi wuli lun 楊子物理論, was an essay on metaphysics written during the Three-Empires-period 三國 (220-280) by Yang Quan 楊泉 (d. after 280 CE), courtesy name Deyuan 德淵. The essay had originally a length of 16 juan, but only fragments are preserved. They were collected by the Qing-period 清 (1644-1911) scholar and publisher Sun Xingyan 孫星衍 (1753–1818) and can be found in his series Pingjinguan congshu 平津館叢書.

Yang Quan hailed from the commandery of Guiji 會稽 (today's Shaoxing 紹興, Zhejiang), but according to other sources from the princedom of Liang 梁國 (close to modern Shangqiu 商丘, Henan). He was never able to gain access to an official position, and instead engaged in philosophical discussions and research in astronomy, the calendar, geography, economy, agriculture and medicine. Of his writings, some passages are preserved of a book called Taiyuanjing 太元經 or Taixuanjing 太玄經 (an imitation of Yang Xiong's 揚雄 Taixuanjing 太玄經, original size 14 juan, fragments collected by Ma Guohan 馬國翰 in his Yuhanshanfang jiyi shu 玉函山房輯佚書), of his collected writings (wenji 文集; 2 juan), (parts of) the rhapsodies Wuhu fu 五湖賦, Zanshan fu 贊善賦, Zhiji fu 織機賦, Canfu 蠶賦, Yangxing fu 養性賦 and Caoshu fu 草書賦 have survived, as well as a text called Qingci 請辭 (see Yan Kejun's 嚴可均 collection Quan Sanguo wen 全三國文).

In his arguments, Yang Quan often referred to older or contemporary writers, in particular from the book Fuzi 傅子. For this reason some editions mixed up these two books, for instance, the encyclopaedic collection Yilin 意林 from the Tang period 唐 (618-907). The Qing-period editor Ye Dehui 葉德輝 (1864-1927) carefully separated the two texts from each other. The surviving fragments of the Wulilun are also found in the series Longxijingshe congshu 龍溪精舍叢書, Hanxuetang congshu 漢學堂叢書 and Huangshi yishu kao 黃氏逸書考.

The book describes Yang's concept of nature and touches many issues in fieldwork and the trades. He defines the slow process of ploughing and sowing as the root of agriculture, and the hurried process of harvest as its ends. He maintains that the character of the soil was an important precondition of cultivation, yet scholars did usually not pay attention to the many types of soil. Yang establishes half a dozen of soil categories with designations similar to concepts in geomancy (fengshui): "tortoise-and-dragon body" (guilong ti 龜龍體), "appearance of unicorn style" (qifeng mao 麟風貌), "force of bow and crossbow" (gongnu shi 弓弩勢), doushi 鬥石, shuzhang 舒張, bisai 閉塞, yinzhen 隱真 (good), jingmao 景卵 (bad), haoying 膏英 (good) and jijiao 塉角 (bad). The way of cultivating of the soil was thus to be adapted to its quality, in order to achieve the best results, with high stalks, long ears and large grains. Yet the seasons would also influence the readiness of the soil to accept seeds. Yang thus says, "warm and steamy air would expand the soil, while the cleansing autumn winds helped to close it."

Yang also shortly describes water wheels (fanche 翻車) used to irrigate fields and orchards. The use of them allowed even children to bring into effect the work of a hundred persons. He acknowledged that the construction of boats (goulu 䑦𦪇) was the masterly business of craftsmen. In relation to the wider nature, Yang compared the spider webs or beehives with the miraculous products of craftsmen. The conception for the artwork, like round or square, came out of the master's heart, and the skill out if his hands. Without refined skills and excellent ideas, no such work would be possible. Yang also mentions a vehicle with a compass (zhinanche 指南車) or the famous sword of Ruan Shi 阮師, and some aspects of medicine.

Water was the element which "established" (li 立) Heaven and Earth, while "breath" (qi 氣) completed (cheng 成) them. "Breath" could be divided into pure and turbid, and in fact, water was also a kind of breath, but "lighter than the breath of earth and stone". From this assumption it can be seen that qi was rather to be perceived a kind of dense or less dense matter. Each object was a spontaneous (ziran 自然) accumulation of breath/matter (qi ji 氣積), or a transformation of breath into a vessel (qi taohua 氣陶化). The density of this accumulation was defined by the dispersion (boliu 播流) of Yin 陰 and Yang 陽. The earth therefore had a shape, but Heaven, as an expression of the revolving "originary breath" (yuanqi 元氣) had no physical structure (tian wu ti 天無體) and just possessed "brightness" (haoran 皓然) as a feature. Yang believed that "bright Heaven" represented the "original breath/matter" (hao tian, yuan qi ye 皓天，元氣也). In the form of dense water, matter constituted heaven and earth (li tiandi zhe, shui ye 立天地者，水也), while different modes of density generated various objects (cheng tiandi zhe, qi ye 成天地者，氣也). As to the human body, it was additionally endowed with wisdom (zhi 智). The length of life depended on the capacity of wisdom as well as on the mode of nourishment. Yang was thus clearly influenced by Daoist practices and warned not to eat too much grain to avoid diseases and to prolong life. The universe itself was a limitless "expanded night" (xuanye 宣夜, a concept of Qie Meng 郄萌). Yet Yang also maintained that objects or creatures came into being by receiving "breath" (wu shou qi er han sheng 物受氣而含生).

Yang rejected the belief that living beings were in possession of a soul. He used the analogy of an extinguished fire that leaves no flame. Man lived because he had obtained breath, and would die if his essence was consumed (ren han qi er sheng, jing jin er si 人含氣而生，精盡而死). Yang thus stands in the tradition of the Later-Han-period 後漢 (25-220 CE) philosophers Huan Tan 桓譚 (23 BCE-56 CE) and Wang Chong 王充 (23 BCE-56 CE) and stood in opposition to the popular religion of Buddhism that assumes the existence of extra-bodily factors. Yang Quan likewise rejected the assumption that all objects had come out of nothing (xuwu 虛無, wu 無) which was part of the Daoist conception of the universe and was vividly discussed by the "School of the Mystery" (xuanxue 玄學) during the third century. Yang directly criticized the "pure talks" (qingtan 清談) of his contemporaries and maintained that they would indulge into discussions about the single hair of a tiger, but not have an idea about the pattern of its fur. Their disputes were "just like the noise of croaking frogs or chirring cicadas".

Of Yang's theories on human nature, not much is known. He criticized that there were persons with the appearance of a saint (Yao 堯) and the behaviour of a tyrant (Jie 桀). In the political sphere, Yang seems to have inclined towards a less rigorous government which would prohibit the influential clans or court cliques to oppose the imperial power.