本文試圖分析郭象之心性理論，指出：（1）郭象所說之「性」其實並不是萬有現實中的差異之性，而是理想中的本然之性。群生會因知、欲之引誘，而背離、破壞此性；必須排遣知、欲之影響，才能復歸此真朴之性。（2）而「心」則擁有二面性。心是知、欲的發動者，是群生破壞本性之元凶；但心也可以無心自忘，使群生歸復原有之本性。因此，「性」雖然是價值標準，「心」才是能抉擇方向的實踐主體。（3）「無心」的工夫指向一忘而又忘的超越境界；郭象認為，群生若不是在忘境之中，就不是真正的適性逍遙。「無心」便是檢驗逍遙境界的唯一標準。（4）郭象也以「神」概念來表述「心」以及其無心境界。聖人境界即是究極的無心之境；凡人唯有透過聖心之無心境界，才能在忘境中自得逍遙。

This article analyzes Guo Xiang's concept of xin (mind) and xing (nature). His thinks of nature as one's original and ideal state, rather than the difference that exists in the universe. The temptation of knowledge and desires are the main cause of every being's deviation from their nature, and only by eliminating their influence can one return to their natural state. Mind is the trigger of knowledge and desire, the thing that is to blame for disturbing nature, but it can also forget itself and reaches the state of inexistence, bringing all beings back to their nature. Therefore, although nature serves as the value standard, mind is the actor that decides one's direction. No-mind is the supreme state reached by continuous forgetting, so a being can never be truly free if it has not forgot itself completely. Guo Xiang also explains mind and no-mind through the concept of shen (spirit). The realm of shengren (sages) equals the realm of no-mind; only in the extreme realm of forgetting can one rid themselves of all limits and achieve true freedom.