一般人通常都會認為道德是我們的義務，它具有規範性（normativity）：一方面，道德對於我們的行動具有約束力，它要求我們如何行動（甚至是無條件的要求）；另一方面，道德對於我們的行動也具有推動力，它提供我們行動的理由（甚至是充分的理由）。然而，道德之規範性的根源何在？傳統上，獨斷理性論（dogmatic rationalism）設法以規範事實保住道德義務之約束力，但似乎無法適當說明其推動力。而道德感性論（moral sentimentalism）則設法以自然良善之情感保住道德規範之推動力，但似乎無法適當說明其約束力。至於康德學派則是主張道德義務之規範性的根源在於意志之自律（autonomy），設法以此兼顧道德規範性的兩個面向。規範性之根源的問題依然是當今道德哲學的重大議題之一，並且除了傳統各家之論據之外，也有一些新說法的提出為此議題的討論增添豐富的材料。在本課程中，我們將閱讀有代表性之哲學家對此議題之見解，分析並檢視其論證是否成立。
People usually think that morality is our obligation, and take moral normativity for granted. Namely, morality makes claims on us; it has binding force even to the extent that it constitutes an unconditional requirement. Morality, furthermore, has motivating force for our actions; it provides them with (sometimes even sufficient) reasons. Notwithstanding, philosophers are wondering about what the source of moral normativity is. Traditionally, dogmatic rationalism, seeking to base morality’s binding force on normative facts, has difficulty giving an adequate account of its motivating force. Moral sentimentalism, on the other hand, seeking to base morality on natural sentiments, has difficulty giving an adequate account of its binding force. This leads Kantianism to identify the source of moral normativity with autonomy, and takes it as the solution to the question why morality has both binding and motivating force. The problem of moral normativity remains one of the central issues of contemporary moral philosophy. Indeed, philosophers have been focusing on this issue and presenting a number of new arguments. In this course, we will read and examine critically some of their important works on the issue of moral normativity.