柯思嘉德式的公共理由觀

Abstract

如果理由在本質上是公共的，那麼在某個人有某個理由做某個行動的情況之下，其他人也都可以有同樣的理由做該行動。在本論文之中，我會以克莉絲汀•瑪莉恩•柯思嘉德(Christine Marion Korsgaard)的理由論為基礎，來回答關於理由的公共性的哲學問題。這些問題包括：(1)「理由在本質上具有公共性」這個命題的涵義為何？(2)「理由在本質上具有公共性」這個命題如何可能被證成？(3)如果「理由在本質上具有公共性」這個命題能夠被證成，那麼這對我們而言會有什麼實踐的蘊含？為了回答這些問題，我會闡明柯思嘉德的哲學計畫與她為了證成該命題而提出的三個理由公共性論證──私有理由論證、互動論證與規範地位論證。並且，我會系統性地整理、分析與回應其他哲學家針對這些論證所可能提出的批評。與此同時，我會藉由批判、修改與補充柯思嘉德的理由論的部分內容，以發展一個更為完善的柯思嘉德式的公共理由觀。最終，我在本論文之中所試圖證成的是，作為在柯思嘉德的哲學計畫之中的最重要的部分的理由公共性論證，在該計畫的其他部分都成功的情況之下，會是健全的論證。

If reasons are essentially public, then if someone has a reason for doing a certain action, everyone else can have the same reason for doing that action. In this thesis, I answer the philosophical questions concerning the publicity of reasons based on Christine Marion Korsgaard’s theory of reason. These questions include: (1) What is the meaning of the proposition “reasons are essentially public”? (2) How can the proposition “reasons are essentially public” be justified? (3) If the proposition “reasons are essentially public” can be justified, then what are its practical implications for us? In order to answer these questions, I explicate Korsgaard’s philosophical project and her three arguments for the publicity of reason — the private reason argument, the argument from interaction, and the argument from normative standing — that she makes to justify that proposition. Moreover, I systematically collate, analyze, and respond to the criticisms that other philosophers may have on these arguments. Meanwhile, I develop a more complete Korsgaardian conception of public reason by criticizing, revising, and supplementing parts of Korsgaard’s theory of reason. Ultimately, what I attempt to justify in this thesis is that the arguments for the publicity of reason, as the most important part of Korsgaard’s philosophical project, will be sound arguments if the other parts of that project are successful.