在找朋友的时候，意见相同的固然可以做朋友，意见相反的也没有什么妨碍。而且从相反的方面看问题，更可避免片面性，所以古人有“相反相成”之说。——徐特立 When looking for friends, those who have the same opinion can be friends, and those who have the opposite opinion will not be hindered. Moreover, looking at problems from the opposite side can avoid one sidedness, so the ancients said that "opposites complement each other"—— Xuteli