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Cheng Hao and Cheng Yi were among the pioneers of Song Dynasty Neo-Confucianism, and they are often credited with its formal creation along with Zhu Xi and several other scholars. The two brothers were sometimes referred to as "The Two Chengs" (), or individually as "Cheng the Elder" () and "Cheng the Younger" (). They dealt extensively with cosmology in their studies, applying Neo-Confucian principles to their studies of celestial bodies. In particular, the brothers identified and applied the principle of Divine or Natural Order, called "li", to that of "Tian", the Heavens, as their original and guiding power. Hao established schools at Fugou and Songyang (in modern Dengfeng). Throughout his life he promoted the view that study and scholarship were means to making men sages, once writing: "The studies of a superior man must arrive at sagacity [sage-hood] and "then" upon his own intellect; in the case of not arriving at sage-hood but upon his own intellect, all is lost." Hao died in 1085 at the age of fifty-three.