The concept of duality plays a significant role in many mythological systems by illustrating the balance between opposing forces, such as good and evil, light and dark, or creation and destruction. This duality often manifests in deities that embody both aspects, suggesting that harmony arises from their interplay. Mythologies convey moral lessons, emphasizing that the coexistence of these dualities shapes the world. For instance, the Yin-Yang in Chinese philosophy epitomizes how contrasting elements are interconnected, ultimately reflecting the complexities of life.