I work and teach in metaphysics, value theory, and philosophy of science. My research can be divided into three areas:
1/ Some of my research addresses metaphysical questions about the nature of individuals, quantities, and space-time. In each case I use symmetry arguments to motivate theses of a structuralist flavor (papers 1, 2, 3, 6, 10, 16). In other work I examine the epistemology of these symmetry arguments (papers 7, 8, 17).
2/ Another line of research involves second-order questions about the nature of metaphysics. In earlier work I focused on grounding and its application to various metaphysical debates (papers 4, 5, 9). More recently, I've been developing an anti-realist view of metaphysics motivated by a normative argument (papers 11, 14, 15).
3/ A third line of research uses the same normative argument to motivate anti-realist views in other domains. Some of this work develops a kind of ethical anti-realism and examines its applications (papers 12, 13, 19). In related work I'm developing a pragmatist conception of truth, justification, and objectivity (papers 20, 21).
Papers in progress
In which I argue that objectivity is a normative notion (twice over).
In which I motivate a broadly pragmatist view of inquiry, truth, justification, and meaning.
In which I argue that there are no right or wrong answers to questions of AI ethics, because they turn on which ethical concepts to use and there is no right or wrong answer to that.
Publications
In which I argue that school closures during the Covid-19 pandemic were a moral catastrophe.
In which I outline the method of symmetry and its application to metaphysics.
In which I describe how to be a relationalist, and while doing so develop a non-factualist account of measurement and distinguish two species of metaphysical possibility.
In which I discuss issues of egalitarianism and privilege that arise in Karen Bennett's book Making Things Up. (For an invited symposium in Philosophy and Phenomenological Research.)
In which I raise a problem for metaphysical realism and suggest a return to a Goodmanian view that the world is a structureless mess onto which we project our own categorizations, not something with categories already built in.
In which I ask: out of all the many entities coincident with a person, that differ only in their essential profiles, which ones matter? I use nonidentity cases to shed light on this question.
In which I develop a familiar argument against normative non-naturalism, to the effect that non-natural properties would have no "normative authority" over us.
In which I argue that the notion of ground can be significantly deflated and still do useful work in philosophy.
In which I argue that the world is a purely qualitative mosaic. Here is the postscript, coauthored with Jason Turner.
In which I develop and defend a version of the Principle of Sufficient Reason, one that entails that every truth is necessarily true.
In which I argue that symmetry is an epistemic notion (twice over).
In which I discuss cases where ignorance is inexpressible (e.g. ignorance of absolute position, quiddities, and haecceities) and argue that the ignorance consists in an inability to identify things by way of their natures.
In which I survey a number of arguments for each view (including the bucket argument, Leibniz shift arguments, and symmetry arguments) and conclude that the case for relationalism is strong. Here is the teaching and learning guide.
In which I argue that the notion of ground is suitable for formulating a variety of metaphysical theses, including physicalism.
In which I argue that ground is an irreducibly plural notion: these are grounded in those. Cases of plural grounding include individuals and quantities like kilograms.
In which I motivate and defend comparativism about quantities like mass.
In which I discuss substantivalism in the context of the General Theory Relativity, and argue that we do not yet have a satisfactory substantivalist theory.
In which I argue that (fundamentally speaking) there are no such things as individuals.
Teaching
I teach undergraduate and graduate classes. I also supervise PhD dissertations and undergraduate honors theses. If you would like me to write a letter of recommendation for you, please let me know as early as possible so that we can plan accordingly. To write an effective letter I will need to follow your progress for some time.
Below is a list of previous courses. Those up to 2016 were taught at Princeton; those since 2017 were taught at UC Berkeley.
Graduate seminars
2021 Spring: Pragmatism
2018 Fall: First-Year Seminar (with John MacFarlane)
2018 Spring: Why is There Anything Except Physics? (with Geoffrey Lee)
2015 Fall: Metaphysics (with Boris Kment)
2014 Spring: Symmetry, Structure, and Spacetime
2013 Spring: Medieval, Early Modern, and Contemporary Work on Substance (with John Morrison)
2011 Spring: Hyperintensional Metaphysics (with Boris Kment)
2009 Fall: The Structure of the Physical World
Undergraduate courses
Since 2014 many of my undergraduate courses have used a "levels system". This is a series of assignments that students complete at their own pace through the semester; see here for an example. Since 2016 the assignments have typically involved constructing argument maps; see here for an introduction to argument maps. I have now accumulated a stock of assignments and maps for these courses, please email me if you would like access to them.
2020 Spring: Phil 5 Science and Human Understanding; Phil 128 Philosophy of Science
2019 Fall: Phil 100 Philosophical Methods
2019 Spring: Phil 100 Philosophical Methods; Phil 125 Metaphysics
2018 Fall: Phil 5 Science and Human Understanding
2018 Spring: Phil 128 Philosophy of Science
2017 Fall: Phil 5 Science and Human Understanding
2016 Spring: Phi 321 Philosophy of Science
2014 Fall: FRS 187 Philosophical Analysis Using Argument Maps (led by Simon Cullen)
2014 Spring: Phi 203 Introduction to Metaphysics and Epistemology
2013 Fall: Phi 318 Metaphysics
2012 Fall: Phi 201 Introductory Logic
2012 Spring: Phi 321 Philosophy of Science
2011 Fall: Phi 203 Introduction to Metaphysics and Epistemology
2011 Spring: Phi 201 Introductory Logic
2009 Fall: Phi 203 Introduction to Metaphysics and Epistemology (with Gideon Rosen)
2007 Summer: Ethics (at NYU)
PhD supervision
Currently supervising dissertations by:
Previous dissertations supervised: