This article considers an apparent Achilles heel for Kant’s transcendental idealism, concerning his account of how synthetic a priori knowledge is possible. The problem is that while Kant’s distinctive attempt to explain synthetic a priori knowledge lies at the heart of his transcendental idealism, this explanation appears to face a dilemma: either the explanation generates a problematic regress, or the explanation it offers gives us no reason to favour transcendental idealism over transcendental realism. In the article, I consider G. E. Moore’s version of the problem, which I argue has not yet received an adequate response. Instead, I offer a way out of this dilemma by focusing on the normativity rather than the metaphysics of the mind.

本文认为康德的先验唯心主义有一个明显的致命弱点，即关于他对综合先验知识如何可能的说明。问题在于，虽然康德解释先验综合知识的独特尝试是其先验唯心主义的核心，但这种解释似乎面临两难境地：要么解释产生有问题的倒退，要么它提供的解释让我们没有理由赞成先验唯心主义胜过先验现实主义。在文章中，我考虑了 GE Moore 的问题版本，我认为它尚未得到足够的回应。相反，我通过关注规范性而不是心灵的形而上学来提供摆脱这种困境的方法。