"Heaven" (tian 天) is an important concept of Chinese philosophy, especially in Confucianism. During the Shang 商 (17th to 11th cent. BCE) and Zhou 周 (11th cent.-221 BCE) periods, Heaven was offered sacrifices as the highest deity and lord of all other deities or spirits (shen 神).
Heaven was seen as a force controlling the world, including society and state. In oldest times, Heaven was a kind of impersonal high ancestral deity (tiandi 天帝), as can be attested in the Shang period oracle bone inscriptions. Life and death, fortune and poverty depended upon the will of Heaven. Confucius 孔子 (c. 551-c. 479 BCE), the great philosopher of the late Spring and Autumn period 春秋 (770-5th cent.), therefore asked whether his illness could be blamed to Heaven, and his disciple Zigong 子貢 explained that his master had been endowed by Heaven unlimitedly.
Among all humans, the ruler as the "Son of Heaven" (tianzi 天子) had the most intimate relationship with Heaven. Heaven had bestowed upon him the "Heavenly mandate" (tianming 天命), allowing him to rule, and supported him in this responsible position. The ruler was, on the other side, also obliged to take over this rule with the necessary feeling of responsibility. He had to avoid at all means to make his people suffering by devastation, exploitation and natural disasters.
In a later tradition, especially in the teachings of the philosopher Mengzi 孟子 (372-289 BCE), the people is seen as "Heaven's eyes and ears". It was the utmost duty of a ruler to serve his people, and whenever the people moaned or rebelled, it was high time to change politics. "Whatever the people desires – Heaven will accord it", is an important expression of this thought to be found in the Western Zhou period book Shangshu 尚書 "Book of Documents".
The early Warring States period 戰國 (5th cent.-221 BCE) philosopher Mozi 墨子 (c. 470-391 BCE) was of the opinion that his concept of "universal love" corresponded to Heaven's love to the people. Whoever followed the intention of Heaven, wouldbe rewarded, and whoever opposed it, would suffer punishment.
In the elegy Tian wen 天問 "Questions to Heaven", part of the collection Chuci 楚辭 "Poetry of the South", Heaven is regarded as an ultimate instance to which questions are asked regarding the nature of man and the universe, but in the end, Heaven is not answering these substantial questions.
On the other hand, Confucius sometimes also doubted that Heaven had a greater influence on daily life. He therefore said, "Does Heaven speak? The four seasons pursue their courses, and all things are continually being produces, but Heaven does not say anything." This is in accordance with many statements in the ancient Classic Shijing 詩經 "Book of Songs", in which Heaven is not seen as a supernatural power influencing daily life. Confucius therefore rarely spoke of Heaven and preferred lecturing on man and society. "His discourses about man's nature, and the way of Heaven, cannot be heard", as one disciple said.
When the science of astronomy developed during the Warring States period, scholars became more aware that the natural world had barely any connection with the human world, and therefore the late Confucian philosopher Xunzi 荀子 (c. 316-237 BCE) expressed his doubts about Heaven's relation to virtuous rulers as Yao 堯 and bad rulers as Jie 桀. The concept of the "Heavenly mandate" was from then on still used as a formula, but was not any more a substantial belief.
The Han period 漢 (206 BCE-220 CE) was the last great epoch of what modern persons would call "superstition". The short-lived Qin dynasty 秦 (221-206 BCE), condemned because of its excesses in exploiting labour force from the population, was seen as a mirror of a government that run counter to the will of Heaven. The philosopher Dong Zhongshu 董仲舒 (179-104 BCE) combined the teachings of Confucius with cosmological speculation and re-established a clear connection with the emperor and Heaven. The Son of Heaven's performance in government would be rewarded or punished by Heaven.
The influence of "August Heaven" (huangtian 皇天), "Bright Heaven" (haotian 旻天) or "Supreme Heaven" (shangtian 上天) on governmental affairs was widely analyzed in the so-called apocryphal classics (chenwei 讖緯) where it is said that – depending on the political performance of a ruler – omina and portents appeared to signify excellence or failure of a ruler.
The Tang period 唐 (618-907) writer Liu Yuxi 劉禹錫 (772-842) clearly separated this "political" Heaven from the that of nature (the sky). The Neo-Confucians of the Song period 宋 (960-1279) instrumentalized Heaven again as a natural element of highest virtue that imposed its order, the "Heavenly order" (tianli 天理), upon creatures and the human character. While Confucius had been of the opinion that only sages as the mythological emperor Yao had corresponded to the will of Heaven, the Neo-Confucians interpreted the Heavenly order as inherent in the character of all humans so that everyone had the potential to become a "sage" of highest virtue. All humans were thus part of a universal Heaven that encompassed all things in the universe as the "greatest extension" (taiji 太極).
The philosopher Zhang Zai 張載 (1020-1077) saw Heaven as the primary form of substance, the "great emptiness" (taixu 太虛) that reigned the universe before the world came into being. Man and Heaven were in the eyes of Cheng Hao 程顥 (1032-1085) identical, and the "will of Heaven" was not any more directed towards a ruler, but it was included in the heart and mind of each individual person.