本研究探究拉崗的無意識主體理論，並根據拉崗所進行的心理分析實踐，闡述其中的教育意涵。拉崗以「回歸弗洛伊德」為取向，針對自我心理學之「自我」概念提出批評，他在「鏡子階段」論述中指出：自我之形塑乃是以想像的疏離同一性之運作方式，構成了自我與擬似者之間的錯識結構。當想像域關聯於倫理學時，拉崗將超我的概念轉化為一種客觀的裝置，即極權式的執鞭者能夠以自身之工具化作為藉口，迫使受害者在痛苦和羞辱中達到其自身之主體化的目標。為了分解想像性自我的鈕結，拉崗以象徵的功能提出了無意識主體的理論。他透過對索緒爾之語言學的轉借，使得文字不再具有符號的指義功能，而是進行著記號的指延純粹運作性。主體因而不再是意義的主人而被文字化為符指，在轉代詞「我」所呈現的陳述主詞與宣告主體的分離與分裂當中，主體乃是具有大它者之激進異質性的無意識主體。據此，在教育意涵中，拉崗以大它者之功能所進行的至高實踐，不但修正了鏡像之無限性的非本真實踐，並且鑽透了鏡映之哲學循環的本真實踐，而使得教育學之論述維繫於分析師的「存在之匱乏」此一政策。 / Based on Lacanian psychoanalytical practice, this research discusses his theory of subject of the unconscious and tries to elaborate latter’s implication of education. Along the path of “Return to Freud”, Lacan criticizes the concept of Ego that is the theoretical core of ego psychology. He traces the genesis of ego back at the mirror-stage and describes the imaginary structure of ego as following: narcissitic formation of the ego is the result of misrecognition between ego and the semblable. When combining the Imaginary with Ethics, Lacan retranslates Freudian concept of superego as the objectivized equipment, and analyzes fully the totalitarian effect of this objectivization that refuses its subjectivization. Totalitarian subject is the pure instrument in his instrumentalization, and forces the pain and humiliation onto the victim to help him to accomplish his subjectivization. In order to untie the knot of the Imaginary, Lacan locates the theory of subject of unconscious in the Symbolic. Borrowing Saussure’s structural linguistics, Lacan paralizes the signifying function that is constitutive of totality of Sign, and emphasizes the pure operativity of the signifier with a hole. Between subject of statement and subject of enunciation, shifter “I” introduces the division in the subject. In what gapes, subject is the radical heterogeneity of unconscious subject. Centered on this function of Other, Lacan not only rescues analysis from its inauthentic practice, he also maintains training discourse in his policy of “lack of being”. The latter founds the supreme practice that brings the full educational implication.