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A religion that was not part of China during the Song Dynasty was Buddhism.
The most important religious doctrines during the Song dynasty were Neo-Confucianism and Daoism. Neo-Confucianism revived the principles of Confucianism that previously prevailed in ancient China. Positions in important government roles were based on merit and officials had to take the complex civil service examination to be part of the government. High moral was at the base of this doctrine. Daoism was based on the idea that humans had spiritual energy that harmonized the body and the mind, producing a healthy living.