精神分析對這個時代最重要的貢獻，無非是顛覆了人與語言的關係，也就是人作為居住在語言當中的「說話存在」的定義。語言並非單純只是表達與溝通的工具，從內在的獨白、日常的閒聊，一直到精神病的胡言亂語，這樣的語言從來都不表達甚麼。那麼，當語言不是被當成語言使用，當語言不是用於傳達意義、不是用於溝通時，那樣的語言究竟有甚麼用？或者反過來問，當語言、文字已經完成任務，表達了它們所承載的意義時，所剩下來的是甚麼？7精神分析與文學的共通點正在於它們都是沒有用、沒有價值的語言實踐。但也因為它們是沒有用的語言實踐，因此更能彰顯出語言與書寫的真正功能。本文從拉岡學派的精神分析所論之語言與書寫的功能，反思德希達所提出的文學剩餘性的問題，並由此探討精神分析與文學的關係以及現代文學的轉向。

The most important contribution of psychoanalysis to the modern era is nothing more than the subversion of the relation of man to language, i.e., the definition of man as “speaking being” who lives in language. The language thus conceived is no longer an instrument of expression or communication. Most of our everyday speeches, such as soliloquy and gossip, are not made to express our intentions nor to convey specific messages. And in extreme cases, such as in the free association of psychoanalysand or in the disarticulated speech of psychotics, the words are even deprived of meaning. What is common between psychoanalysis and literature is precisely that they are language practices that have no value or utility. The language is used to say nothing. But this is why they are particularly apt to draw attention to the true function of speech and language. This paper, starting from the Lacanian conception of the function of language and writing, re-examines the question formulated by Jacques Derrida about the “remainder” (restance) of literature, and from there, analyses the relation between psychoanalysis and literature, as well as the reorientation of modern literature.