The four subjects of education advocated by Confucius: literature, conduct, loyalty, and good faith

The four classic subjects of ancient education: the 诗经 shī​jīng, the 尚书 shàng​shū, the 礼记 lǐ​jì, and the 乐经 yuè​jīng

The four feminine virtues of ancient China: fidelity, physical charm, propriety in speech, and efficiency in needlework

Refers to the classification of the Buddha's teachings into four categories: sudden, gradual, secret, and unfixed