Li Dong 李侗， Zhu Xi’s 朱熹 teacher， proposed “sitting in quietude to purify the mind and apprehend Heavenly Principle”， a viewpoint akin to Xie Liangzuo’s 谢良佐. “Ti” 体 means embodying the Dao， and “ren”认 means internalizing the Great Dao as one’s own virtue. Heavenly Principle is the ontological substance of the Dao， and its apprehension denotes spiritual communion with the Dao itself. In Zhu Xi’s exposition， “apprehension” entails deliberation and intellectual inquiry， physical and mental practical verification， spiritual cultivation in quietude before emotional arousal， and merging into the ceaselessly immanent flow of the Dao. Yet Zhu Xi also held that such apprehension borders on observing the mind with the mind； it requires deliberate effort and is not the highest state of effortless self-cultivation. Influenced by Chen Baisha陈白沙， Ming Confucian Zhan Ganquan 湛甘泉 advanced the idea of “apprehending Heavenly Principle in all circumstances”. Central to its cultivation connotation are impartiality， non-forcing and non-forgetting， learning， reflection， discrimination and practice， mental concentration， sincerity and reverence， and complete spiritual detachment. “In all circumstances” covers mind and affairs， inner and outer， motion and stillness， silence and perception， a state that is both omnipresent and all-embracing. Zhan Ganquan’s doctrine represents the culmination of Song-Ming spiritual praxis on apprehending Heavenly Principle. It integrates intentional endeavor and non-action， unifying the innate and the acquired， implicitly responding to Zhu Xi’s critiques. As close friends， Zhan and Wang Yangming王阳明 engaged in academic debates： Yangming criticized Zhan’s theory for leaning toward external trivialities， while Zhan argued Wang’s innate knowing doctrine overemphasized inward introspection. He also faulted later Yangming followers for taking spiritual awareness as innate knowing and confusing it with emotional consciousness. To some degree， Zhan’s teaching can complement Wang Yangming’s theory and make up for its theoretical limitations.