Kant thought that our minds had no perceptual access to the world as it but our perception was in a way warped by the limitations and idiosyncrasies of our minds. Kant calls the real world, independent of our minds, the noumenal world. The world we perceive is the phenomenal world. John claims that our total experience is a joint product of the noumenal world and the phenomenal.

Ken介绍了嘉宾Peter Gilgen，他是康奈尔大学的教授。彼得·吉尔根触及了康德时代的哲学领域。在18世纪中期，理性主义者(如莱布尼茨和笛卡尔)捍卫了一个严格的形而上学体系，他们声称这个体系完全建立在理性之上。然而，康德的哲学在很大程度上是对这一传统的一种反应。康德声称休谟的怀疑论把他从“教条的沉睡中”唤醒，而理性主义者无法迎接怀疑论的挑战。受牛顿的启发，康德希望将“形而上学置于科学的稳固基础之上”，并在此过程中写出了《理性批判》。

Kant claimed that if an unnoticeable glass that distorted sight were put right in front of our eyes for all our life, we wouldn't be able to recognize that our sight was distorted. We can't know whether our perception as a whole is distorted by such "an invisible glass". Our perception apparatus contributes to our perception. John comments even though we see a solid desk, we know that the desk is made of atoms, atoms in turn by quarks and that the desk is mostly space. Is this the kind of perceptual distortion Kant had in mind? Peter Gilgen explains that according to Kant, our perceptual blockade is deeper than what science can reveal. Even time and space are categories our perception apparatus bring into this world.

尽管康德认为本体不是直接可用的，但每个人都有一个共同的感知架构来描述这个世界。(例如，每个人都有空间和时间的概念。)同样，他否认休谟对因果关系的怀疑(这种怀疑认为没有证据表明因果规律应该成立)，并声称因果关系是现象世界的一种属性。

Kant thought that even the idea that we are free is enough to grant us moral freedom and responsibility. Our intuition to judge something as not right deems morality a genuine possibility.