本文擬從訓詁、義理並進的方式重探「天」的意義架構。從古文字、天文、曆法、神話等各種證據考察，殷人「天」的觀念已經相當豐富，一則植根於自然天象循環，二則以日月時辰命名天子，三則借用象徵人體的「人」字突顯其首腦部位以譬喻「天」字，四則以尞祡饗祭表達對上帝的尊崇，五則重視天子之登天。「天」字造字之原理實已為後世天人思想的遠源，尤堪注意。日與月亮影響人類生活至鉅，不但為農業所重視，也是殷、周帝王用以宣示政治綱領的最高觀念。殷人尚陰，周人尚陽，本諸天象，施用於政治教化，恐非後人託古附會，而是歷史事實。周滅殷商，承襲殷人天道終始循環之理，進一步標舉了主變、尊崇陽剛的精神，貴陽而賤陰，突顯「初、終」循環的自然之理和動態規律，並引申喻指人事的成壞興革，強調天命靡常，更注入尚德的意志，規範天命為帝王所獨有。借馮友蘭「五義」之說，殷人之天，實以自然及物質之天為基礎，又蘊含若干主宰意味，且具有浪漫神話色彩。周人加強了人文意識，注入尚德、尚陽、剛健、主變的成分，既涵括了主宰、自然的意識，已為戰國以降義理之天、運命之天打下基礎。

This paper attempts to reconstruct the meaning system of “Tian,” especially in its development from the Yin to the Zhou dynasty, by incorporating the ancient people’s knowledge of astronomy and the calendar through reinterpreting the historical records in early Chinese classics, canons and excavated texts. By revisiting the work done on ancient Chinese civilizations by leading scholars like Wang Guowei, Herrlee G. Creel, Chen Mengjia and Dong Zuobin, the author also reexamines the theory of the “five meanings of Tian” declared by Feng Youlan. The author consequently concludes that as early as in the Yin dynasty, “Tian” carried multiple meanings. The graph itself is a metaphor featuring the human head. The nature of “Tian” reflected by the celestial phenomena is a never ending cycle—the names of the heavenly stems and celestial phenomena were used to name the kings, while the kings burned their sacrifices to show their respect to “Tian.” The Zhou people inherited part of the philosophy of “Tian” from the Yin people, but emphasized the solar, masculine or positive power as well as the political morality of “Tian” which is the main spirit of the mandate of heaven.