本文試圖處理牛頓（Newton, Isaac）與萊布尼茲（Leibniz, Gottfried Wilhelm）在時間觀上的爭論，這兩種時間觀最大的差異在於：前者主張真正的時間是一種絕對時間（absolute time），它可獨立於事物存在，並同時承載事物，後者則主張時間不過是事物的規定性，離開了事物也就沒有時間可言。其中，萊布尼茲在他與克拉克（Clarke, Samuel）的書信中提出了對絕對時間觀的批評。而筆者則希望藉由釐清兩者對於時間的真正觀點，以進一步評判萊布尼茲的批評是否公正、若其批評是正確的，絕對時間觀是否仍有修正的可能性，以及萊布尼茲的時間觀是否會遭遇不同的困境等問題。於是本文將分成以下四個部分：壹、牛頓的絕對時間觀，貳、萊布尼茲的批評與相對時間，參、充足理由律與同一律，肆、相對時間的問題。前兩個部分分別對牛頓的時間觀、萊布尼茲對它的批評以及萊布尼茲本身的時間觀做一個分析與整理。而在第三個部分當中，筆者嘗試對牛頓的絕對時間觀提出修正以擺脫萊布尼茲論證的攻擊。最後，在第四個部分當中，筆者將提出萊布尼茲的相對時間觀可能會遭遇的困難。

In this paper I address the debate between Newton and Leibniz on the concept of Time. The biggest difference between their distinct conceptions of time is that whether time is absolute or relative; Newton holds that real time is absolute, which is independent of the existence of things; on the contrary, Leibniz holds that time is relational to the things, which implies that there is no time, were there no things. In this debate, Leibniz provided his argument against Newton in the letters to Clarke. So my research is mainly based on the correspondence between Leibniz and Clarke. I hope to clarify the true standpoint of both and furthermore to judge whether Leibniz's criticism is right. And if Leibniz is right, is it possible to modify Newton's conception of time, but otherwise also to maintain the essence of his conception? And finally, I hope also to inspect Leibniz's conception, to see whether it is confronted with different difficulties. Therefore this paper contains four parts: First, the Newtonian conception of absolute time. Second, Leibniz's criticism and the conception of relative time. Third, principle of sufficient reason and principle of identity. Finally, the difficulty of the relative conception of time. In the first two parts, I analyze Newton's and Leibniz's conceptions of time respectively and also Leibniz's criticism. In the third part, I attempt to modify the Newtonian conception to avoid Leibniz's criticism. In the final part, I attempt to point out the difficulty of the Leibnizian conception.