The so-called Song-Yin xuepai 宋尹學派 "School of Song Xing and Yin Wen" was one of the philosophical schools of the Warring States period 戰國 (5th cent.-221 BCE). Its main representatives were Song Xing 宋銒 (also called Song Jing 宋徑, Song Jing 宋鋞 or Song Rong 宋榮, 385-304) and Yin Wen 尹文 (360-280). Both were scholars in the Jixia Academy 稷下 in the state of Qi 齊. The 18 chapters long book Songzi 宋子 is lost, but from a short book called Yinwenzi 尹文子, some fragments are preserved. It might be that the chapters Neiye 内業, Baixin 白心 and Xinshu 心術 in the book Guanzi 管子 originated by Song Xing or disciples of his. According to the book Zhuangzi 莊子, Song Xing stressed the importance of an objective analysis of things.
In the field of politics, Song Xing emphasized that a ruler had to make use of the best advisors, to personally live in austerity, and accordingly not waste state funds, and not to exploit his ministers nor his people. Like Mozi 墨子, Song Xing warned against a war of conquest. Warfare should only be a means of defence. This is the reason why Song Xing is often mentioned together with Mo Di 墨翟 (Mozi). Concerning the often discussed relation between objects and designations, Song Xing stressed that a thorough investigation of things was necessary to understand their objective existence. Only then it would be possible to give a name to objects that was appropriate to their reality and would exclude subjective perception. All objects would then be given an appropriate designation. Appropriate designations would lead to proper standards, and with such conditions, the sage ruler would be able to govern without activism. This interpretation bring Song Xing in the vicinity of Daoist thought. The enlighted man would have to make himself tree of traditions, to liberate things from embellishment, to get rid of the influence of others, and to be released from the dullness of the masses. The personal desires would then become less and smaller, and nobody would strive for fame and fortune.
Yin Wen studied at the Jixia Academy, together with Song Xing, Peng Meng 彭蒙 and Tian Pian 田騈. After King Min's 齊湣王 (r. 323-284) assassination he took refuge in Guyi 谷邑 and later on went to the state of Wei 衛. Yin Wen represented the Daoist style of inactive government (wuwei 無為), which he thought would result in a peaceful realm. Military activities were to be reserved for defence, and the ruler had to adhere to economy and sparingness. His interpretation of the dichotomy of appearance and designation he stated that shape (xing 形) and appearance (shi 實) are something objectively existing, and that designations (ming 名) are a concept of pointing at those objective realities. The designations are thus derived from the real shapes, and serve to define matters in speech and practical activities. Action, in a responsive and confirmative way, regulates the designations. Shape is the basis for designations, and all objects must have designations, while designations can also exist that not correspond to an existing object. Even things without a designation mut have shape and colour. Anyone who desires to speak about anything in the world has therefore first to distinguish what he is talking about and to objectively define things, in other words, to "rectify the names" (zhengming 正名). Only after preparing such a general base, it is possible to concretely speak about concrete measures in politics.
Tang Shaojie 唐少杰 (1996). "Song-Yin xuepai 宋尹學派", in: Zhuzi baijia da cidian 諸子百家大辭典, ed. by Feng Kezheng 馮克正, Fu Qingsheng 傅慶升, p. 960. Shenyang: Liaoning renmin chubanshe.
Tang Shaojie 唐少杰, Li Yaming 李亞明, Li Binghai 李炳海 (1996). "Song Xing 宋銒", in: Zhuzi baijia da cidian 諸子百家大辭典, ed. by Feng Kezheng 馮克正, Fu Qingsheng 傅慶升, p. 26. Shenyang: Liaoning renmin chubanshe.
Li Binghai 李炳海, Tang Shaojie 唐少杰 (1996). "Yin Wen 尹文", in: Zhuzi baijia da cidian 諸子百家大辭典, ed. by Feng Kezheng 馮克正, Fu Qingsheng 傅慶升, p. 29. Shenyang: Liaoning renmin chubanshe.