MenciusBy: Mencius Mencius was one of the great philosophers of ancient China, second only in influence to Confucius, whose teachings he defended and expanded. The Mencius, in which he recounts his dialogues with kings, dukes and military men, as well as other philosophers, is one of the Four Books that make up the essential Confucian corpus. It takes up Confucius's theories of jen, or goodness and yi, righteousness, explaining that the individual can