| 摘要: | 本論文主要探討人際互動中產生的利己與利他行為動機，分析理性與情感之間的交互影響。從心理利己主義、倫理利己主義，與利他主義之間的關係，闡明經由理性支持利他行為，將其確立為道德義務。
主要依循Thomas Nagel對「他人實在性」的認知動機，以及將自身視為「眾人之一」的理性自覺，透過所論述的「理性一致性」與「本然的觀點」等理論，詮釋道德判斷的基礎。這些道德判斷不但來自個體視角的感知經驗，更透過理性所推論出的普遍義務。同時參考Thomas Michael Scanlon所提出的「沒有人能合理地拒絕」原則，使道德義務成為普遍且正當的規範要求；Derek Parfit認為，唯有當我們的行動符合普遍性原則，方能真正維繫對自我與他人的尊重。進一步依循Henry Sidgwick的「不偏不倚」原則，得以理解道德義務應建立於具備理性可證成的倫理立場，其道德判斷必須超越個體主觀的偏好與情感，進而採取達到普遍快樂的客觀立場。據此，本文依循「沒有人能合理地拒絕」原則與「最樂觀」原則，置於 Nagel「本然的觀點」視角轉換架構，旨在協助個體於道德行動的權衡中，超越當下的自利考量，實現對當代與未來世代福祉的理性關懷。是以，本論文試圖建構一個利他的「合理性理由–道德義務–倫理價值」的理性利他實踐架構。依「合理性理由」確立道德義務的動機正當性，「道德義務」作為行動的規範基礎，「倫理價值」則奠基於理性義務的普遍快樂價值。
最後，依 Nagel 所揭示的「荒謬感」，試圖以突現理論轉化為最優倫理價值祈嚮。依循《周易》中「順應性命之理」與「成性存存」的義理，使人在理性與倫理實踐中實現自我與關懷他人，於生命實踐中展現內在利他主義。
;This thesis investigates the rational foundation of altruism and argues that moral obligations can be justified through reason rather than emotional impulses. While sympathy may spark altruistic actions, reason offers a more stable and universal basis for consistent moral behavior. By comparing psychological egoism, ethical egoism, and altruism, this study highlights how altruism can be grounded as a rational moral duty.
This study draws on Thomas Nagel’s moral philosophy, including his concepts such as the recognition of the other person’s reality, the rational awareness of being “someone among many,” the principle of rational consistency, and “the view from nowhere.” These ideas form the basis for understanding moral judgment not merely as a subjective response but as a rational recognition of universal moral duties that extend even to future generations. Incorporating T. M. Scanlon’s theory of “no one could reasonably reject,” it argues that moral obligations must be justifiable within a shared rational framework. Derek Parfit argues that only by acting on universally willable principles can we uphold respect for self and others, and ensure moral consistency and impartiality. Such rational principles ground moral action and advance a more just society. In accordance with Henry Sidgwick’s principle of impartiality, moral obligation should rest on a rationally justifiable ethical standpoint—one that transcends subjective preferences and aligns with the objective moral demands of universalistic hedonism. Therefore, this study proposes a triadic model of altruistic ethics, consisting of reasonable motivation, moral obligation, and ethical value. Reason legitimizes moral motivation, obligation provides the normative foundation, and ethical value arises from fulfilling rational duties aligned with universalistic hedonism.
Finally, inspired by Nagel’s notion of “the sense of absurdity”—the tension between subjective experience and objective perspective—this thesis suggests such reflection can motivate ethical action. Through emergence theory and the Book of Changes, it argues for a synthesis of rational self-realization and care for others, ultimately grounding altruism as a reflective ethical practice. |
