I study the nature of time, space, and possibility, and the relationships between things, their parts, and their qualitative properties. I also work on probability and decision theory, and I’m interested in category theory and its applications to philosophy. My work applies technical tools to traditional philosophical questions.


  • General Dynamic Triviality Theorems (with John Hawthorne)
    Forthcoming in Philosophical Review
  • Qualitative Grounds
    Forthcoming in Philosophical Perspectives
  • Temporary Safety Hazards
    Noûs 2015
  • Indefinite Divisibility
    Forthcoming in Inquiry
  • Groupthink (with John Hawthorne and Lara Buchak)
    Philosophical Studies 2014
  • On Where Things Could Be
    Philosophy of Science 2014
  • Possible Worlds and the Objective World
    Philosophy and Phenomenological Research 2013
  • Actuality for Counterpart Theorists
    Mind 2013
  • The Structure of Gunk: Adventures in the Ontology of Space
    Oxford Studies in Metaphysics 2008

Work in Progress

  • Composition as Abstraction
  • Possible Patterns (with John Hawthorne)
  • Quality and Quantifiers
  • Space-Time Categories
  • How Much is at Stake for the Pragmatic Encroacher
Photo by Ken Lund [CC BY-SA 2.0]


I regularly teach Philosophy 450 (Intermediate Logic), which is about the limits of what can be said, proven, calculated, or counted. We study deep human discoveries about the infinite, the indescribable, and the impossible. If you've taken intro logic (or suitable courses in math, computer science, or linguistics) and you're interested in taking 450, contact me.

I also regularly teach graduate seminars and undergraduate classes in metaphysics, epistemology, philosophy of religion, philosophy of language, and philosophy of math.

In Spring 2017 I'll be teaching a new intro seminar on artificial intelligence.

Spring 2016

Past Courses

By Tuxyso (Own work) [CC BY-SA 3.0 (], via Wikimedia Commons

Contact Me

University of Southern California, School of Philosophy

Office Hours (Spring 2016)

Tuesday, 12:30–2pm
227 Stonier Hall