"Aphorisms" ("Cheng") is part of the Mawangdui silk scrolls which is closely related to Huang-Lao Taoism, once categorized by Tang Lang as one of "The Yellow Emperor's Four Canons". Unlike "Laozi, The Yellow Emperor's Four Canons" focused on yin/yang, emphasized the equal importance of the way of heaven and the way of earth, combined "seasons" with the thought of "penalty/reward," showed the balance between yin and yang, and saw yin/yang as the crucial agent to correspond the way of the heaven and the way of all men. Such a doctrine became mainstream in the late Period of Warring-states, and the concepts about "seasons" and balance between "penalty and reward" were embodied in "Guanzi's" discourses on yin/yang, the Qi Legalist thought, and the Military Strategist thought. Even "Hanfeizi" of the late Period of Warring-states evolved and transformed from this Legalist thought. This article is meant to explicate this equal importance of the way of heaven and the way of earth, which is actually about "seasons," and show how they were integral to the politics, society, and scholarly thoughts of the Period of Warring-states through the yin/yang embodiment of "seasons." Here we intend to discuss how "Aphorisms" reflected the thought of yin/yang and how the link between yin/yang and "seasons" was utilized in Military School and Legalism.