This thesis aims to make an analysis of the concepts of &amp / #8216 / existence&amp / #8217 / . It also constructs four new definitions based on the concept of &amp / #8216 / effect&amp / #8217 / for different concepts of beings. By reasoning based on these definitions and some pre-suppositions, a foundation for an axiomatic system of ontology is tried to construct.

The main objective of this study is to shed light on some difficulties involved in the formulation of the problem of contingency in Leibniz&rsquo / s philosophical system. Leibniz&rsquo / s mature philosophy is characterized by the solutions he proposes for this problem, and the ontological ideas underlying or assisting them. &lsquo / The problem of contingency&rsquo / refers to the tension between his conceptual containment theory of truth and his claim that true existential propositions &ndash / that is, propositions which concern actual individuals &ndash / are all contingent. Though Leibniz does not seem to have one definite theory of contingency, two general lines of thought can nevertheless be discerned from his fragments on propositions and propositional truth. The first one is the infinite analysis theory, which is regarded in general as Leibniz&rsquo / s real theory of contingency, and the other is a theory of necessity, providing a division between absolute and hypothetical modalities. This thesis is not a study on the question whether Leibniz did really manage to solve the problem, but rather an attempt to trace the problem to its logical and ontological origins, and redefine it under a relatively simple form. It is first shown that Leibniz&rsquo / s theory of propositions relies heavily on his ontological conception of modalities, which covers the idea of a division between pure possibility and actuality / and then this idea is shown to be reflected on the logical level as a division between essential and existential truths. Finally it is argued that the two lines of thought and some peculiar characteristics of Leibniz&rsquo / s conception of modalities bring us to the conclusion that his real problem is the (deliberate) inability of his propositional calculus to express the difference between truths of reason (essential truths) and truths of fact (existential truths) as a logical structural one.

早期馬克思的思想，尤其是對人的存在與問題，受到黑格爾與費爾巴哈很大的影響。但是馬克思並不侷限於兩位先哲的理論框架，而是將自己的理論深深紮根在人這個實際的個體上，馬克思真正關注的是人在現實社會中的處境，並致力於將理論化為實際行動。 身處在資本主義社會與現代性的洪流裡，「異化」的感受深深地衝擊我們，馬克思從異化的角度，試圖去建構一個沒有異化的自由人聯合體。自由人聯合體是馬克思運用啟蒙以來的主體理性與分析資本主義的歷史走向，所建構出來的理想社會。針對資本主義中異化人的處境，馬克思企圖將資本主義社會中的原子式個人轉為聯合起來的自由人，並且打造一個聯合勞動、彼此互助的自由人聯合體。雖然許多人對他的理論有褒有貶，但是卻不能否認，馬克思理論的啟發性與影響力。 關鍵字：馬克思、費爾巴哈、黑格爾、異化、類存在、自由人聯合體 / In the early thoughts of Marx, especially for human existence and problems, are effected by Hegel and Feuerbach very much. However, Marx didn’t limit himself to the theory frame of these two philosophers but rooted his theory in human being individual deeply. Marx real concerned about the situation of people in the real society and he was devoted himself to turn his theory to action. Being in the mighty torrent of capitalism society and modernity, the feeling of “ alienation” strikes us heavily. Marx tried to establish an unity of freedom without alienation from the point of alienation. The unity of freedom is an ideal society which Marx used reason of subject from the Enlightenment Age and analyzed the historical trend of capitalism. For the situation of alienated being in the capitalism, Marx tended to change atomic individual to united free people and made an unity of freedom which people work and help each other. Though many guys disagree with his theory, they still can’t deny that the enlightenment and effect of theory of Marx. Key words: Marx, Feuerbach, Hegel, alienation, being existence, unity of freedom