康德的超驗觀念論與經驗實在論

Kant's Transcendental Idealism and Empirical Realism

康德哲學雖然稱為超驗觀念論，但其立場與一般觀念論分別甚大。在經驗層面，康德其實接受實在論，他更提出了觀念論的反駁，試圖證明外在世界存在。事實上，康德的超驗觀念論與經驗實在論不單是兩個相容的理論，甚至是一個理論的兩個不同面向。本文論證經驗實在論才是康德的存有論立場，而超驗觀念論則是其知識論框架。本文首先分析康德的模態範疇，解釋康德的存在概念只能應用在時空領域之內，然後論證本體或物自身「不存在」的結論。本文區分兩種不同類型的外在事物，從而澄清康德在什麼意義下是存有論的實在論者和知識論的觀念論者。

Although Kant characterizes his philosophy as transcendental idealism, his position differs fundamentally from ordinary idealism. On the empirical level, Kant subscribes to realism, even offering a proof for the existence of the external world with the refutation of idealism. In fact, Kant's transcendental idealism and empirical realism are not just two compatible theories, but two different aspects of a unified theory. The paper argues that Kant's ontological position is determined by his empirical realism, whereas transcendental idealism represents his epistemological framework. By analyzing Kant's modal categories, the paper shows that Kant's concept of existence is only applicable within the spatiotemporal realm, leading to the conclusion that noumena or things in themselves cannot be said to exist. It further distinguishes between two kinds of external things, a distinction which helps clarify in what sense Kant is an ontological realist and epistemological idealist.