Chinese tradition remembers the Warring States as the age of the Hundred Schools of Thought, when philosophical and religious argument flourished precisely because no single authority could suppress it. Confucius himself died in 479 BCE, just before the period's conventional start, but his teachings were carried forward and reshaped by Warring States successors: Mencius argued that human nature is fundamentally good and that a ruler's legitimacy depends on the people's welfare, while Xunzi took the opposite view, that human nature is inclined toward disorder and must be actively corrected through ritual and education, a disagreement that structured Confucian thought for the rest of Chinese history.
Alongside Confucianism, Daoism took shape in this period through texts attributed to Laozi and, more securely, through Zhuangzi, whose writings favored spontaneous accord with the natural way, or Dao, over the effortful ritual self-cultivation Confucians recommended. Mozi founded a rival school, Mohism, arguing for impartial care toward all people regardless of family ties, against the graded affections of Confucian ethics, while Legalist thinkers such as Han Feizi treated strict law and state power, not moral cultivation, as the only reliable foundation for order. This philosophical ferment ended, in effect, with the Qin unification, whose Legalist state briefly suppressed rival schools outright, but the period's texts, above all the Analects, the Mencius, the Zhuangzi and the Han Feizi, remained foundational to Chinese religious and ethical thought for the following two millennia.