What was the name of the more important school in the pre-Qin period?

One of the most important schools of thought in the pre-Qin period was called Confucianism.

Extension:

Confucianism is the most influential and far-reaching school among the pre-Qin philosophers. It was initiated by Confucius at the end of the Spring and Autumn Period and was highly respected by Confucian scholars in previous dynasties. Confucius' remarks were compiled into The Analects by disciples, which is the main basis for studying Confucius' thoughts. Confucianism takes benevolence as the center, and advocates "respecting ancestors and respecting martial arts", "rites and music", "benevolence and righteousness", "loyalty and forgiveness" and "the golden mean". Politically, it advocates "benevolent governance" and "rule by virtue" and attaches importance to ethical and moral education.

Confucianism is the core of traditional culture in China, and it is also the theoretical basis for maintaining the autocratic rule of feudal monarchs. Confucianism and absolute monarchy constitute the two main contents of China's ancient political history.

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