Since the Periods of Spring-Autum and Warring-States, the doctrines of yin/yang and five elements have been combined, expanded and transformed in nature. In view of the surviving and recently excavated documents from the the Pre-Qin Period and the Han Dynasty, the combined doctrines basically followed the Huang-Lao Taoist orientation of "compiling with the natural rules of yin/yang," focusing on the fluctuaiton of nature, rotation and the timely manipulation of governmental affairs. In the Han Dynasty, Dong Zhong-shu developed them on two tracks, balancing between the Huang-Lao Taoist princples of natural fluctatiaon, alteration and conquests and the Legalist concept about the superior ruler and inferior subjects.