 Leibniz’s argument is clever at the outset: he bypasses the thorny problem of determining whether Newton’s idea of absolute space commits him to thinking of space as a substance—a view, incidentally, which Newton explicitly considers and rejects in De Gravitatione (Newton 2004: 21–2)—by presupposing only that Newton thinks of space as existing independently of objects and their relations. If space is indeed independent in this way, then it would seem that God faces a choice: when creating the world, or matter, why place (e.g.) the earth in one particular part of space rather than any other? The parts of space, independently of all objects and all relations, obviously do not differ from one another in any respect at all, so it would seem that one could not even theoretically devise a reason for placing the earth anywhere in particular, as opposed to anywhere else . (This argument, incidentally, does not depend on our having the capacity to refer to places within empty space.) But since space exists, with all its places, independently of the earth and everything else, then God must indeed have some reason to place the earth in one place rather than another—for Leibniz, even the divine will is inert independent of any reason for (as it were) moving in one direction rather than another. Finally, Leibniz argues that he himself avoids this problem by asserting that space is nothing above and beyond the objects in the world and all possible relations amongst them (hence he holds a kind of modal relationalist view, in more modern terminology). God faces no problematic choice on this view, since space does not exist prior to the creation of the world, or of material objects: to create objects with spatial relations is ipso facto to create space itself, for it is nothing over and above objects and their relations. If you like, space for Leibniz just is a way of conceptually grasping all objects and all possible relations amongst them, all at once. Time, similarly, is a way of grasping the whole series of events that have characterized history. Clarke’s reply is somewhat disappointing: he blocks Leibniz’s inference by simply denying that the divine will must have a reason to place (say) the earth in one place rather than another (Clarke and Leibniz 1717: C 3: 5). The PSR is not violated in this case, according to Clarke’s interpretation of it, because it requires only this: if the earth appears in one place rather than another, there must be a reason that it appears there, and the reason in this case is simply the divine will; there is no further question about why the divine being made a particular choice rather than another. In the quotation above, Leibniz speaks of the Newtonians as endorsing “the reality of space”, which Leibniz regards as “chimerical”. This remark highlights another important aspect of Leibniz’s conception of space and time, one that is often ignored in contemporary discussions, which tend to emphasize Leibnizian “relationalism” in opposition to Newtonian “absolutism”. Leibniz’s view of space and time connects intimately with broader aspects of his metaphysical positions: unlike ordinary physical objects, which are constituted by their parts (they are discrete), and which exhibit features that involve internal distinctions amongst those parts, he thinks of space and time as continuous and homogeneous. Leaving aside the monadology, as he does in his correspondence with Clarke, this means that for Leibniz, it is physical objects that are real things; space and time are merely “ideal” or abstract entities whose continuity and homogeneity signal this special status. It is not merely that space and time are nothing over and above the events and relations of objects that exist in our world; it is also the case that they are ideal: they depend in some way on the human mind for their existence. Or so Leibniz seems to suggest. This aspect of his view would become of central importance to later (e.g. Kant’s) conceptions of the Leibniz-Newton debate on the nature of space.