柏拉图和以自然哲学为代表的哲学快乐论伦理学在反对纵欲主义上是“盟友”。然而,他们采取的哲学治疗的策略却基本相反,一个是加法,一个是减法。这导致他们相互批判,甚至因此相互认为是主要敌手。柏拉图在有的对话录中也尝试过快乐主义,用它建立道德。但是他最终完全否认这一路径,这是因为他在这种“元伦理学”的背后看到十分严重的理论和实践的威胁。这里的分歧暗示了所谓“古今之争”的对峙的基本原因——主观价值论还是客观价值论。 Plato and philosophical theory of happiness represented by natural philosophy Ethics is “ally” against obsessions. However, the strategies they adopted for philosophical treatment were basically the opposite. One was addition and the other was subtraction. This led them to criticize each other and, as a result, mutual recognition as the main rival. Plato also tried hedonism in some dialogues and used it to establish morality. However, he eventually denied this path completely because he saw very serious theoretical and practical threats behind such “meta-ethics.” The differences here suggest the basic reason for the confrontation of the so-called “ancient-modern war” - the subjective value theory or the objective value theory.