Guyer argues that the traditional distinction between "one-world" and "two-world" interpretations of transcendental idealism is misleading; everyone has always recognized that there is a distinction between our representations and things external to them, and the question is only what Kant says about the latter. Does he strip them of spatiotemporality while leaving their existence untouched, as he says in the Prolegomena, or not? Guyer claims that Kant's position is clear: there are things in themselves, independent of our representations, but they are not spatiotemporal, even though that is how we represent them. He then argues that recent attempts to reconstruct his argument without this dubious premise cannot do without it.