行先知后

对“知”“行”关系的一种认识。王夫之等人在“知”“行”关系问题上提出了“行先知后”的主张。王夫之承认对人伦日用之道的体认与践行是相互关联的，但就先后而言，只有先“行”才能获得“知”。“行”是“知”的来源，对“知”起着决定性的作用。能“行”必然对所行之事有所“知”，但能“知”却未必能“行”。

First Action, Then Knowledge

The term represents one interpretation of the relationship between "knowledge" and "action". Regarding the relationship between "knowledge" and "action", Wang Fuzhi and others argued that "action precedes knowledge". Wang acknowledged that an understanding of the principles underlying human relations in everyday life is interrelated with the application of these principles, but in terms of sequence, only through "action" can one obtain "knowledge". "Action" is the source of "knowledge" and has a decisive impact on "knowledge". If one can "act", one inevitably "knows" about one's actions, but the ability to "know" does not necessarily translate into the ability to "act".

引例 行焉而后知其艰，非力行焉者不能知也。（王夫之《四书训义·论语九》）（践行之后才知道其中的艰难，若没有努力践行就不能知晓。）

Only after acting can one know the difficulties involved; without efforts to act one cannot know. (Wang Fuzhi: Explicating the Lessons of the Four Books)