refers to the classical schools of thought, e.g. Confucianism 儒[ru2] represented by Confucius 孔子[Kong3 zi3] and Mencius 孟子[Meng4 zi3], Daoism 道[dao4] by Laozi 老子[Lao3 zi3] and Zhuangzi 莊子|庄子[Zhuang1 zi3], Mohism 墨[mo4] by Mozi 墨子[Mo4 zi3], Legalism 法[fa3] by Sunzi 孫子|孙子[Sun1 zi3] and Han Feizi 韓非子|韩非子[Han2 Fei1 zi3], and numerous others
