Syllabus: Convention and Modality


The topic of this seminar is reductive theories of modality. Everyday modal notions include possibility ("Dukakis might have won the election"), necessity ("It is necessary that bachelors are male — i.e., bachelors are necessarily male"), counterfactual conditionals ("Dukakis would have won the election if he had not ridden on the tank"), and quantification over possibilities ("there are three ways to win this chess match"). Modalities provide many philosophical challenges. There are epistemological challenges: how do we know what might or must be the case, given that all we ever observe is what is the case? Metaphysical challenges: In virtue of what are modal statements true? Can they (and should they) be made to fit into a naturalistic or scientific ontology? Logical/semantic challenges: what analysis of modal statements can be given, which captures the logical behavior of these statements but does not make the epistemological and metaphysical challenges insurmountable?

Some prominent accounts of the modalities we will study (roughly in this order) include the following:

P is necessarily true iff ...
... P is true in all possible worlds (possible worlds theory)
.... P is true in all rearrangements of the actual world (combinatorialism)
... the fiction of worlds says that P is true in all worlds (fictionalism)
... P's truth is guaranteed by linguistic conventions (conventionalism)


We'll begin by discussing parts of David Lewis's book On the Plurality of Worlds, which is out of print. I've xeroxed the relevant bits, which are in the TA room. If you can acquire a used copy of this contemporary classic, I would recommend doing so. We'll then discuss parts of D. M. Armstrong's A Combinatorial Theory of Possibility, which is only available in hardback. Anyone who wants to order a copy should let me know, and I'll tell the bookstore how many copies to order. Otherwise we'll xerox. The rest of the readings will be available for copying; I'll place them in the TA room.

I'll split the readings into two folders, "Main" and "Supplement". I have a third folder of readings, "archive", which I won't put in the TA room, but if you see a paper on my modality bibliography (see below) that you are interested in, and which is in neither of the folders, see me; I may have a copy that will save you a trip to the library.


Four weeklies (40%) plus a term paper (60%). The weeklies should be short and focused. You can email them to me. They should be on something related to what we're doing in class, but needn't be on articles assigned for class. You must do two by 2/28/00, another two by 4/10/00, and the last one by the final day of class. I will distribute a bibliography of readings on modality, which includes a number of abstracts. This should help you out in choosing supplementary readings for the course, and research for your final paper.


Note: for complete bibliographic information see the modality bibliography.

  1. Lewis's possible worlds
  2. Required reading

    • David Lewis, On the Plurality of Worlds, sections 1.1-1.3, 1.6-1.9, all of chapter 2, and sections 3.1 and 3.2.
    • Scott Shalkowski, "The Ontological Ground of the Alethic Modality", section 2.

    Optional reading

    • Divers, "The Analysis of Possibility and the Possibility of Analysis" (esp. § III)
    • McGinn, "Modal Reality"
    • Roy, "Worlds and Modality"
    • Charles Chihara, The Worlds of Possibility: Modal Realism and the Semantics of Modal Logic, chapter 3.
  3. Combinatorialism
  4. Required reading

    • D. M. Armstrong, A Combinatorial Theory of Possibility, chapters 3-8.
    • D. M. Armstrong, A World of States of Affairs, chapters 9, 10.
    • David Lewis, "Critical Notice of D. M. Armstrong, A Combinatorial Theory of Possibility"
    • Fraser MacBride, "Could Armstrong Have Been a Universal?"
    • Scott Shalkowski, "The Ontological Ground of the Alethic Modality", section 3.

    Optional reading

    • Holly Thomas, "Combinatorialism and Primitive Modality"
    • Holly Thomas, "The Principle of Recombination and the Principle of Distinctness"
  5. Fictionalism
  6. Required reading

    • Gideon Rosen, "Modal Fictionalism"
    • Gideon Rosen, "A Problem for Fictionalism About Possible Worlds"
    • Ted Sider, "The Ersatz Pluriverse" section IV

    Optional reading

    • Daniel Nolan, "Three Problems for "Strong" Modal Fictionalism"
    • Daniel Nolan and John Hawthorne, "Reflexive Fictionalisms"
    • Stuart Brock, "Modal Fictionalism: A Response to Rosen"
    • Peter Menzies and Philip Pettit, "In Defence of Fictionalism about Possible Worlds"
    • Bob Hale, "Modal Fictionalism: A Simple Dilemma"
    • Bob Hale, "A Desperate Fix"
    • Gideon Rosen, "Modal Fictionalism Fixed"
    • Harold Noonan, "In Defence of the Letter of Fictionalism"
    • John Divers, "A Modal Fictionalist Result"
    • John Divers, "Modal Fictionalism Cannot Deliver Possible Worlds Semantics"
  7. Conventionalism
    1. Classic views
    2. Required reading

      • A. J. Ayer, Language, Truth and Logic, chapter 4
      • Selections from Arthur Pap, Semantics and Necessary Truth

      Optional reading

      • Rudolf Carnap, (something from Meaning and Necessity or The Logical Syntax of Language)
      • Wilfred Sellars, "Inference and Meaning"
      • A. C. Ewing, "The Linguistic Theory of A Priori Propositions"
    3. The translation objection
    4. Required reading

      • Casimir Lewy, chapter 1 from Meaning and Modality
      • John Ibberson, "Necessity by Convention"
    5. The contingency objection
    6. Required reading

      • Casimir Lewy, "Logical Necessity"
      • Valerie and Richard Routley, "Some Bad Arguments for and against Conventionalism"
    7. Quine
    8. Required reading

      • W. V. O. Quine, "Truth by Convention"
      • W. V. O. Quine, "Carnap on Logical Truth"
      • W. V. O. Quine, "Two Dogmas of Empiricism"

      Optional reading

      • Neil Tennant,"Conventional Necessity and the Contingency of Convention"
      • Paul Grice and Peter Strawson, "In Defense of a Dogma"
      • Paul Boghossian, "Analyticity Reconsidered"
    9. The challenge from the necessary a posteriori
    10. Required reading

      • Alan Sidelle, chapters 1 and 2 from Necessity, Essence, and Individuation: a Defense of Conventionalism
      • David Chalmers, selections from The Conscious Mind

      Optional reading

      • Saul Kripke, selections from Naming and Necessity
      • Hilary Putnam, "The Meaning of ‘Meaning'"
      • Lloyd Humberstone and Martin Davies, "Two Notions of Necessity"
      • Robert Stalnaker, "Assertion"
      • Eli Hirsch, "Metaphysical Necessity and Conceptual Truth"
    11. The challenge from de re modality
    12. Required reading

      • W. V. O. Quine, "Three Grades of Modal Involvement"
      • Kit Fine, "The Problem of De Re Modality"

      Optional reading

      • Tom McKay,"Essentialism in Quantified Modal Logic"
      • Terence Parsons, "Grades of Essentialism in Quantified Modal Logic"
    13. Recent reductive theories
    14. Required reading

      • Christopher Peacocke, "Metaphysical Necessity: Understanding, Truth and Epistemology"
      • Mark Heller, "Property Counterparts in Ersatz Worlds"

      Optional reading

      • Peter Sullivan, "The ‘Modal Extension Principle': A Question About Peacocke's Approach to Modality"
      • Christopher Peacocke, "The Principle-Based Conception of Modality: Sullivan's Question Addressed"