Abstract: The meanings of “Huangtian”(皇天),“Mintian”(旻天) and “Cangtian”(苍天) are almost divine in the Book of Songs (Shi Jing 诗经),and “Haotian”(昊天) is both divine and natural.With a philosophic tendency,the divine meaning of the word “Shangtian”(上天 the upper sky or heaven) has been weakened.At the same time,its connotation has been naturalized and spatialized,getting closely correlated with the light of the sun and the moon and being opposite to “Xiatu”(下土 the lower earth).The opposition of“Tian”(天sky) and “Tu”(土earth) can be regarded as an early form of the concept of “Tiandi”(天地heaven and earth).“Tiangao”(天高higher sky) and “Dihou”(地厚thicker earth),which are presented in the poem The First Moon (Zhengyue 正月) in Xiaoya(小雅),indicates that the concept of heaven and earth has been formed,which should be the concept of the Spring and Autumn Period.From the absolutely supreme god to the concept of “Tiandi” in the relative meaning,the transformation of the concept of “Tian”(天sky or heaven) is a breakthrough in the development of early Chinese philosophy,and its ideological significance is unprecedented in history.

Key words: Huangtian, Mintian, Haotian, Cangtian, upper sky, lower earth, Tiandi