An analysis on “(The reaction between) one Yin and one Yang is called Dao”
HUANG Qing-xuan
(Department of Chinese Languages and Literature, Taiwan Normal University, Taibei, Taiwan, China)
Abstract: The proposition of “The reaction between one Yin and one Yang is called Dao” arouses three issues: the relationship between one Yin and one Yang, the relationship between the Dao and one Yin & one Yang, and whether Dao is monistic or dualistic after all. With the help of the history of Chinese and western philosophy, this paper analyzes these issues and concludes that the proposition of “The reaction between one Yin and one Yang is called Dao” has completely covered the three implications of simplicity, changing, and unchanging of Yi.
Key words: Yin-yang; Dao; monism; dualism; three implications of Yi
二元论与一元论本是西洋哲学的用语。纯粹的二元论或一元论，无论中外，都很少见。17世纪法国哲学家笛卡尔（Rene Descartes)是倡二元论的。他认为精神和物质是两种绝对不同的实体，固然为二元；但他又说二者的本源，是“绝对的实体——上帝”。这又有点像《周易》由阴阳二仪推向太极之道，回到客观唯心主义的一元论了。一元论最主要的有唯心论与唯物论。倡唯心论的如十八九世纪德国哲学家黑格尔（Geong Friedrich Wilhelm Hegel)，主张：“绝对是同一和非同一的同一。”同一与非同一不是有点像阳正、阴负，近乎二元吗？又说：主体是主观的“主体-客体”；客体是客观的“主体-客体”。主体与客体不也近乎二元吗？倡唯物论的恩格斯（Friedrich Engels)以为：哲学上的物质概念是对世界上各种有形存在着的事物的根本特性的最高概括。（参《马克思恩格斯全集》第20卷）。“物质概念”岂不近于“形而上者谓之道”，“有形存在着的事物”岂不近于“形而下者谓之器”吗？道、器犹理、气，不也有人界定为二元吗？西洋哲学如此，我国哲学亦然。说“阴阳”，固可视为二；说“道”，却是一。船山说“《周易》并建乾坤为诸卦之统宗，不孤立也。”为二元论矣。又说“太极者，乾坤之合撰。”又似一元论也。说“理气”，固可视为二元，但程朱多次言“理一分殊”，归于“理一”，故学者颇有以程朱为一元论者。韩康伯承王弼说“无”，为一元“无”本论，却又说阴生于无阴、阳生于无阳，是有无阴、无阳二元矣。二元、一元皆难确立，中外皆然，大致如此。