papers on metaphysics and modality

In (A. Egan and B. Weatherson, eds) Epistemic Modality (Oxford University Press, 2011). The central idea of this paper is that of epistemic space: the space of epistemically possible worlds, or “scenarios”. I explore various ways of constructing this epistemic space — one tied to centered possible worlds, and one tied directly to epistemic notions. And I outline some applications of the framework from this perspective: e.g. to Fregean sense, narrow content, indicative conditionals, and hyperintensionality. This paper was online for 10 years or so before publication, and there’s also an html version with slightly different content. [pdf] [philpapers]

In (T. Gendler & J. Hawthorne, eds) Conceivability and Possibility (Oxford University Press, 2002), pp. 145-200. This paper addresses the epistemology of modality, and argues for a sort of modal rationalism (a priori access to modality). It distinguishes a number of sorts of conceivability, and with these distinctions in hand argues that certain sorts of conceivability plausibly entail sorts of possibility. The second half of the paper addresses potential gaps between the two, and gives a positive argument for modal rationalism. Lots of interesting issues come up along the way. This paper was published in Conceivability and Possibility, edited by Tamar Gendler and John Hawthorne (Oxford, 2002). There have been discussions of the ideas in this paper by Lauren Ashwell, George Bealer, Brian Weatherson, and Stephen Yablo, among others. [html] [philpapers]

Analysis 71:411-19, 2011. This paper argues against the common view that all propositions of the form

are knowable a priori by arguing (via a simple logical proof!) that some are unknowable. Consequences for the correct understanding of apriority are discussed. [pdf] [philpapers]

In (B. McLaughlin, A. Beckermann, & S. Walter, eds) Oxford Handbook of the Philosophy of Mind (Oxford University Press, 2009), pp. 313-335. Expanded version in The Character of Consciousness (OUP, 2010). This long paper gives the fullest and best-developed version of my version of the conceivability argument against materialism using two-dimensional semantics. The focus is especially on the connection between conceivability and possibility and the issue of strong a posteriori necessities. Many objections are addressed! [pdf] [philpapers]

This paper is a reply to three commentaries by Philip Goff and David Papineau, Geoff Lee, and Joe Levine in a symposium on The Character of Consciousness. All three comments focused on the issue of strong necessities (another symposium on the book focuses on issues about the contents of consciousness), so this leads to a usefully unified and coherent exchange. [pdf] [philpapers]

Co-authored with Frank Jackson. Philosophical Review, 110:315-61, 2001. This paper is a reply to Ned Block and Robert Stalnaker’s paper “Conceptual Analysis, Dualism, and the Explanatory Gap”. It doesn’t presuppose knowledge of that paper. It defends from first principles the thesis that there is an a priori entailment from microphysical and phenomenal truths (plus or minus a bit) to macroscopic truths; it addresses Block and Stalnaker’s objections to this thesis; and finally argues that a priori entailment is required for reductive explanation and for physicalism. The paper appears in Philosophical Review 110:315-61, 2001. There have been a number of replies, e.g. by Peter Carruthers, Joe Levine, and Laura Schroeter. A number of the ideas and argument here are developed further in Constructing the World. [pdf] [philpapers]

This paper was my response in a symposium on my book The Conscious Mind in Philosophy and Phenomenological Research in June 1999 (the corresponding precis of the book is also online). The commentators were Sydney Shoemaker, Brian Loar, Chris Hill & Brian McLaughin, and Stephen Yablo, all of whom take a “type-B materialist” position on which there is an epistemic gap between physical and phenomenal, but no modal gap. This gets quickly into issues about the 2-D analysis of a posteriori necessity, and whether there are “strong necessities” that escape it. I argue that there are not, and argue for a sort of modal rationalism. [html] [philpapers]

In (Chalmers, Manley, and Wasserman, eds.) Metametaphysics. This paper is a defense of a broadly Carnapian deflationism about ontological questions. I make sense of a version of Carnap’s internal/external distinction as the distinction between ordinary and ontological existence assertions. I distinguish between lightweight and heavyweight ontological realism and ontological anti-realism, and argue for the latter. I develop a way of making sense of Carnapian frameworks via “furnishing functions” that associate a domain of objects with a world. [pdf] [philpapers]

First published on thematrix.com in 2003, and printed in (C. Grau, ed) Philosophers Explore the Matrix (Oxford University Press, 2005). I argue that even if we are in a Matrix-style simulation, most of our ordinary beliefs about the world are true. The hypothesis that we are in a Matrix is really a metaphysical hypothesis: one according to which physical objects are constituted by computations and all this was designed by a designer (in the next world up). I use this to argue against a sort of Cartesian global skepticism about the external world. [pdf] [philpapers]

In (P. Clayton and P. Davies, eds) The Re-Emergence of Emergence. Oxford University Press, 2006. On different notions of emergence: strong emergence (favored by philosophers), which involves something unpredictable in principle, which is therefore new and fundamental, and weak emergence (favored by scientists), which involves something surprising, which is therefore derivative but important. I give my own favored analyses and cases of these phenomena. [pdf] [philpapers]

Forthcoming in Disputatio. On the metaphysics of virtual reality. I defend a sort of virtual realism and virtual digitalism (on which virtual objects are real digital objects) over virtual irrealism and virtual fictionalism (where virtual objects are fictional objects). With discussion of the definition of VR, of illusions in VR, of the value of VR and Nozick’s Experience Machine, of augmented reality and dreams, of the connection to structuralism and skepticism, and more. This paper will be the subject of a symposium on Disputatio with a number of commentaries and eventually a reply. [pdf] [philpapers]

An excursus from Constructing the World that connects my scrutability framework to the metaphysics of supervenience and grounding. I develop a sort of conceptual metaphysics where metaphysical grounding is constitutively connected to conceptual grounding. [pdf]