Are the facts about numerical identity and distinctness metaphysically fundamental, or do they somehow reduce to more basic facts about reality? In other words: do we need something like the "='' sign to write the book of the world? 1 It's a commonplace that our concept of identity is primitive, unanalyzable; but conceptual simplicity doesn't entail metaphysical fundamentality. On the contrary, since everything is identical to itself and nothing else, one might naturally think that identity/distinctness facts are grounded in purely ontological facts. Hence Nolan (2005, p. 37), elaborating Lewis: "[W]e are happy to think facts about numerical identity supervenes [sic] on what objects there are. It is not as though you have to say what all the objects are, and then which objects are identical to which. Every object is identical to itself automatically.'' Imagine God creating a field of poppies. Once the flowers exist, there's no need for Her to survey the field and stipulate that this poppy will be identical to itself, and distinct from that poppy, that poppy, etc. Intuitively, the identity/distinctness facts come along for free; they seem to be nothing over and above the relevant existential facts.(2) To be a bit more precise, we might put the thought as follows: Every fact of the form A=A is grounded in the corresponding fact that A exists. (1) Similarly, facts of the form A not equal B are grounded in the fact(s) that A and B exist. (2) The plan for the present note is first to problematize this admittedly appealing thought, and then to argue against various possible responses to the puzzle. This second section begins by clarifying the rules of our game, using some familiar "definitions'' of identity to illustrate the crucial distinction between metaphysical and conceptual circularity. I then argue that reductions of numerical identity from qualitative identity and set theory are metaphysically circular for reasons having to do with totality or "that's all'' facts. The paper concludes with a brief reassessment of Lewis's famous dictum that identity is utterly simple and unproblematic.
