本論文探討前期海德格中「實存論的獨我論」的主張，並且試著從西田幾多郎哲學的角度來反省這個問題。文獻依據主要在海德格的《存在與時間》(1927) 與西田的〈我與汝〉(1932)。文章區分為四個章節，首先（壹）在陳述本文的詮釋方法與獨我論的問題之後，我們接著致力於重構海德格對「他者的經驗」的說明。對海德格來說，我們任何的與存在物的遭遇都是詮釋性的，他者的經驗亦同。我們注意到海德格最先談到他者經驗的地方在手許物的指示關係上，我們鋪陳這個思路（貳），在措詞上特別著重於存在與存在物的差異，「存在論的差異」是理解《存在與時間》的核心。在這裏由手許物的指示關係所指示的「他者」雖然無法窮盡他者的意義，但反而可以顯示世界作為「有意義性」（或譯為「意蘊性」）的基本思路，顯示出由不安的死所滑落的世界的基本形式構造。但是世界的意義並不止於此，對海德格來說，此在的世界是共存在的世界。本文接著（參）分析了，本真的與非本真的「共存在」與「相互共存在」，並且從西田哲學的角度，反省海德格實存論的獨我論的意義。最後（肆）筆者個人的看法在於：西田「無的自覺」的想法可以為現象學所要求的回歸實事本身提供一個可能的思考空間。

In this paper I attempt to throw some light on the basic meanings of "existential solipsism" in early Heidegger and propose some critical response from Nishida’s philosophy. My paper is divided into four sections. After a brief explication of the problematic the article (section one), I then try to reconstruct Heidegger's theory of the encounter with the others in his Being and Time. It is well known that Heidegger breaks the inner-outer distinction of Cartesian philosophy and begins his philosophy from the analysis of existence of Dasein. For Heidegger the encountering with entities as entities, and therefore others as others, is interpretative. The meaning of the other cannot be exhausted through the encounter with the ready-to-hand equipment (section two). Our world is fundamentally shared with the others. Heidegger bases his theory of others on the notion of “being-with” (Mitsein) and “being-with-one-another” (Miteinandersein) and gives a purely descriptive account of our pre-theoretical involvement with the other which constitutes the inauthenticity of our “being-with” and “being-with-one-another”. I reconstruct the path which leading form inauthentic encounter with others to the authentic encounter with others (section three). It is my view that (section four) Heidegger's early philosophy is still a form of solipsism, which should be overcome from Nishida's philosophy of nothingness.