David Chalmers & David Manley 
Metametaphysics [PDF ebook] 
New Essays on the Foundations of Ontology

Metaphysics asks questions about existence: for example, do numbers really exist? Metametaphysics asksquestions about metaphysics: for example, do its questions have determinate answers? If so, are these answers deep and important, or are they merely a matter of how we use words? What is the proper methodology for their resolution? These questions have received a heightened degree of attention lately with new varieties of ontological deflationism and pluralism challenging the kind of realism that has become orthodoxy in contemporary analytic metaphysics. This volume concerns the status and ambitions of metaphysics as a discipline. It brings together many of the central figures in the debate with their most recent work on the semantics, epistemology, and methodology of metaphysics.