dào bù tóng, bù xiāng wéi móu 道不同，不相为谋
Part Ways and Part Company
Travelers heading down different paths do not plan together how to travel. Originally, the saying meant people with different views and beliefs do not seek to work together. Dao (道 way), which originally referred to “road,” is extended to include opinions, beliefs, interests, viewpoints, and guiding principles. Mou (谋 plan), is extended to mean cooperation and collaboration. In order to work together, it is most important to agree upon a set of common goals and principles. Without them, parties cannot collaborate successfully. On the other hand, collaboration should not sacrifice principles. Upholding principles does not mean rejecting cooperation. Rather, it means rejecting unprincipled deal-making. This is true of cooperation among individuals and among countries as well.
Confucius said, “People who differ in their principles do not work together.” That is to say, they follow their own will in their action. (Records of the Historian)
Friends are those who have commonalities. If they differ in principle, what can they share? (Xunzi)