Our conception of logical space is the set of distinctions we use to navigate the world. In The Construction of Logical Space Agustín Rayo defends the idea that one's conception of logical space is shaped by one's acceptance or rejection of 'just is'-statements: statements like 'to be composed of water just is to be composed of H2O', or 'for the number of the dinosaurs to be zero just is for there to be no dinosaurs'. The resulting picture is used to articulate a conception of metaphysical possibility that does not depend on a reduction of the modal to the non-modal, and to develop a trivialist philosophy of mathematics, according to which the truths of pure mathematics have trivial truth-conditions.