在德希達的《明信片：從蘇格拉底到佛洛伊徳之外》(1987)一書中，〈郵寄〉這個文本由許多交換傳遞的明信片所組成。這些收錄於同一文本中的明信片令我們聯想到書信小說中編纂成冊的信件。許多十七、十八世紀的英國與法國書信經典名著構成了書信文類的主要架構，如吉樂哈格的《葡萄牙修女的情書》(1669)、理查生的《潘蜜拉》(1740)與《克萊麗莎》(1747-1748)、葛芬妮的《祕魯公主的情書》(1747)、盧梭的《茱莉，或新伊珞絲》(1761)以及德拉克勞斯的《危險關係》(1782)。面對這些書信文類的前導者，且處於二十世紀傳統書信寫作式微的時代中，是什麼因素促使德希達創作〈郵寄〉這部書信文本呢？〈郵寄〉的書信文本又與傳統書信小說有何不同呢？ 關於這個議題，我所提出的論點是，德希達的〈郵寄〉企圖解構書信文類。〈郵寄〉一方面強化了書信文類特有的書信特質，另一方面又以明信片的郵件傳遞效果取代替換傳統書信小說的書信文類特質。明信片的郵件傳遞效果主要呈現出「傳送終點」與「預期的收信者」這兩種特定規範的不可能性。明信片總是暗示信件傳送過程中「被攔截」與「多元收信者」的可能性。這樣的特質使明信片得以打破囿於最初起點與最後終點做為邊界的直線軌道。如此的突破有助於德希達解構西方知識體系的架構。明信片的郵件傳遞效果動搖了源自蘇格拉底的知識遺產直線傳承，顯示出知識遺產是經由多元讀者所傳遞的，且容許眾多不同的詮釋方法參與其中。多樣性的想法損毀了「原作與衍生」，「在場與缺席」以及「公開與隱私」之間的二元對立邏輯。明信片「半私密，半公開」(《明信片》62)的形式在多樣化所隱含的不確定性之間來回擺盪，游移不定。這種不確定性正是德希達藉由〈郵寄〉這個文本所要強調的。因此，即使身處電信通訊網絡遍佈的時代，德希達依然期望引發「不受拘束的明信片化帝國」(《明信片》104)的可能性。明信片化的意義並非加速書信寫作的「衰微」(《明信片》104)，而是希望能夠不斷地散佈差異產生的可能性。 在本論文中，我從迂迴、延宕與延異這三項特性來闡述明信片的書信特質。這三項特性同時交織於我對〈郵寄〉這個書信文本的討論中。在第一章〈書信文類：強化與替代〉裡，我提出了〈郵寄〉所呈現的似非而是的矛盾，既強化又替代書信文類的特質。書信文類因此被置於差異的迂迴內，而延遲了其文類身份認同的最後裁定。在第二章〈書信他/她者：欲望投射〉裡，我援引拉岡「小寫他/她者」的概念來闡釋書信寫作行為中的自我建構過程。由於寄信者需要缺席收信者的存在以召喚差異的產生，因此寄信者的自我認同總是不斷地在迂迴的信件傳遞空間中被延宕。第三章〈書信寫作：添補的矛盾〉裡，我將德希達對「添補」的概念與書信寫作中添加與替代的效果作了連結。書信寫作彌補了距離造成的溝通差距，同時也以距離替代了最後與缺席收信者真實相遇的那一刻。第四章〈書信交換：Fort Da消失與返轉的遊戲〉中，我比較了佛洛伊德、拉岡與德希達對於fort da遊戲不同的觀察角度。在書信交換的過程裡，當多元讀者的可能性被納入考量時，書信的傳送與接收便會持續地滯留迂迴於讀者的多元閱讀與詮釋，而延遲了到達預定目的地的時間。在第五章〈書信傳承：知識遺產的明信片〉裡，我探討了德希達對於〈郵寄〉中明信片上蘇格拉底與柏拉圖位置返轉圖所做的種種推敲。這些推測暗示了脫離知識體系直線傳承，迂迴而行的可能性。為了再現知識的意涵而創造出的多元詮釋角度會不斷地延宕知識傳承的最終意義。 / In Jacques Derrida’s The Post Card: From Socrates to Freud and Beyond (1987), the part of “Envois” is composed of many exchanged post cards. This collection of post cards reminds us of the letters compiled in epistolary novels. There is a lot of prestige attached to many seventeenth- and eighteenth-century English and French epistolary novels, such as Gabriel de Guilleragues’ The Portuguese Letters (1669), Samuel Richardson’s Pamela (1740) and Clarissa (1747-1748), Françoise de Graffigny’s Letters from a Peruvian Woman (1747), Jean-Jacques Rousseau’s Julie, ou la nouvelle Héloïse (1761), and Choderlos de Laclos’ Les Liaisons dangereuses (1782). These epistolary novels constitute the main frame of the epistolary genre. Then, confronted with the epistolary predecessors, what prompts Derrida to write the epistolary text of “Envois” in the twentieth century, in which the telecommunications networks appear to overpower the importance of writing letters or post cards? What is the difference between “Envois” and the previous epistolary novels? On this issue, I want to argue in my thesis that Derrida’s “Envois” is intended to deconstruct the epistolary genre by paradoxically valorizing and substituting the postal effects of the post card for the generic identities of epistolary novels. The postal effects of the post card primarily invoke the impossibility of the predestined destination and intended receiver. The post card always implies the possibilities of interception and multiple receivers in the process of transmission. In this way, the post card disrupts the linear path confined in the hierarchical opposites between the original departure point and the final destination. This disruption facilitates Derrida’s attempt to deconstruct the construction of knowledge in the Western intellectual genealogy. The postal effects are applied to destabilize the linear succession of intellectual inheritance originated since Socrates. The inheritance is transmitted by multiple readers and hence susceptible to a myriad of interpretations. The binary logic between the original and the derivative, the present and the absent, and the public and the private is undermined in the multiplicity. The form of the post card, which is “half-private half public” (Post Card 62), oscillates in the indeterminacy of multiplicity. The postal effects of indeterminacy aroused in the post card are what Derrida emphasizes in “Envois.” As a result, even in the age replete with the telecommunications networks, Derrida still proposes the possibility of “the unlimited empire of a postcardization” (104). The postcardization does not mean to precipitate the “decadence” (104) of epistolary writing, but it aims to disseminate and recurrently stimulate the possibility of difference. In my thesis, I propose three perspectives to illuminate the epistolarity of the post card: detour, deferral, and différance. They are interwoven in my discussion of Derrida’s “Envois.” In chapter one “Epistolary Genre: Valorization and Substitution,” I propound a paradox that “Envois” simultaneously valorizes and substitutes for the epistolary genre. “Envois” therefore puts the epistolary genre in a detour of difference and defers its determination of identity. In chapter two “Epistolary Otherness: The Object of Desire,” I apply Jacques Lacan’s concept of the object of desire to elucidate the self-construction in the act of writing post cards. The sender’s self-identity is continually deferred in a detour, because s/he requires the absent receiver to evoke his/her difference. In chapter three “Epistolary Writing: Paradox of the Supplement,” I relate Derrida’s concept of the supplement to the paradoxical effects of addition and substitution in epistolary writing. Writing post cards adds to a compensation of the distance, but it also simultaneously substitutes the distance for the final encounter with the absent receiver. In chapter four “Epistolary Exchange: Play of the Fort Da,” I compare Sigmund Freud’s, Lacan’s, and Derrida’s different observations on the fort da game. The fort da movements of epistolary exchanges are interminably deferred in a detour, when multiple readers in the process of transmission are taken into consideration. The multiple readers replenish possibilities of differences with a variety of interpretations. In chapter five “Epistolary Inheritance: Post Card of Intellectual Legacy,” I explore Derrida’s speculations on the scene of reversal copied on the post cards collected in “Envois.” The scene of reversal between Socrates and Plato is speculated to imply possible detours away from the linear succession of genealogy. Different representations of knowledge persistently defer the final determinate meaning of the intellectual inheritance.