The Heart of Yin-Yang (阴阳) Philosophy: 阴 (yīn) is inseparable from its counterpart, `阳 (yáng)`. In Taoist thought, the universe is governed by the balance of these two opposing but complementary forces. 阴 is the force of passivity, coolness, darkness, femininity, and downward movement (like water flowing downhill). `阳` is activity, heat, light, masculinity, and upward movement. Crucially, one is not “good” and the other “evil.” They are interdependent; night cannot exist without day, and shadow cannot exist without light. The goal is not for one to conquer the other, but for them to exist in harmonious balance.