Let ‘monism’ be the view that there is only one basic object—the world. Monists face the question of whether there are also non-basic objects. This is in effect the question of whether the world decomposes into parts. Jonathan Schaffer maintains that it does, Terry Horgan and Matjaž Potrč that it does not. In this paper, I propose a compromise view, which I call ‘Kantian monism.’ According to Kantian monism, the world decomposes into parts insofar as an ideal subject under ideal (...) conditions would divide it into parts, but it does not decompose into parts in and of itself, that is, in an entirely mind-independent manner. After articulating Kantian monism more precisely (Section 1), I present a prima facie case for preferring it over more standard varieties of monism (Section 2). (shrink)