内丹理论将阴阳与人的寿命和成仙为鬼联系起来，纯阳无阴为仙，纯阴无阳为鬼，阴阳相杂为人，人通过修炼，可达纯阳之体而长生不死。
Pure Yang without Yin is the immortal , the opposite is the ghost , mixture of both is human , so human can be pure Yang and become immortals through cultivating .
纯阳之体