•  85
    Information Flow: The Logic of Distributed Systems
    with Jon Barwise
    Cambridge University Press. 1997.
    Presents a mathematically rigorous, philosophically sound foundation for a science of information.
  •  85
    Logical dynamics of belief change in the community
    with Fenrong Liu and Patrick Girard
    Synthese 191 (11): 2403-2431. 2014.
    In this paper we explore the relationship between norms of belief revision that may be adopted by members of a community and the resulting dynamic properties of the distribution of beliefs across that community. We show that at a qualitative level many aspects of social belief change can be obtained from a very simple model, which we call ‘threshold influence’. In particular, we focus on the question of what makes the beliefs of a community stable under various dynamical situations. We also cons…Read more
  •  51
    The scope of Turing's analysis of effective procedures
    Minds and Machines 12 (2): 203-220. 2002.
    Turing's (1936) analysis of effective symbolic procedures is a model of conceptual clarity that plays an essential role in the philosophy of mathematics. Yet appeal is often made to the effectiveness of human procedures in other areas of philosophy. This paper addresses the question of whether Turing's analysis can be applied to a broader class of effective human procedures. We use Sieg's (1994) presentation of Turing's Thesis to argue against Cleland's (1995) objections to Turing machines and w…Read more
  •  50
    Hybrid languages
    Journal of Logic, Language and Information 4 (3): 251-272. 1995.
    Hybrid languages have both modal and first-order characteristics: a Kripke semantics, and explicit variable binding apparatus. This paper motivates the development of hybrid languages, sketches their history, and examines the expressive power of three hybrid binders. We show that all three binders give rise to languages strictly weaker than the corresponding first-order language, that full first-order expressivity can be gained by adding the universal modality, and that all three binders can for…Read more
  •  49
    A Note on Freedom from Detachment in the Logic of Paradox
    with Jc Beall and Thomas Forster
    Notre Dame Journal of Formal Logic 54 (1): 15-20. 2013.
    We shed light on an old problem by showing that the logic LP cannot define a binary connective $\odot$ obeying detachment in the sense that every valuation satisfying $\varphi$ and $(\varphi\odot\psi)$ also satisfies $\psi$ , except trivially. We derive this as a corollary of a more general result concerning variable sharing
  •  44
    Logic, Language and Computation: (edited book)
    Center for the Study of Language and Inf. 1996.
    This volume presents work that evolved out of the Third Conference on Situation Theory and Its Applications, held at Oiso, Japan, in November of 1991. The chapters presented in this volume continue the mathematical development of situation theory, including the introduction of a graphical notation; and the applications of situation theory discussed are wide-ranging, including topics in natural language semantics and philosophical logic, and exploring the use of information theory in the social s…Read more
  •  42
    The rights and wrongs of natural regularity
    with Jon Barwise
    Philosophical Perspectives 8 331-364. 1994.
  •  13
    Journal of Logic, Language and Information 4 (3): 175-176. 1995.
  •  7
    Flexibility in Ceteris Paribus Reasoning
    Australasian Journal of Logic 10. 2011.
    Ceteris Paribus clauses in reasoning are used to allow for defeaters of norms, rules or laws, such as in von Wright’s example “I prefer my raincoat over my umbrella, everything else being equal”. In earlier work, a logical analysis is offered in which sets of formulas Γ, embedded in modal operators, provide necessary and sufficient conditions for things to be equal in ceteris paribus clauses. For most laws, the set of things allowed to vary is small, often finite, and so Γ is typically infinite.…Read more
  •  3
    General Dynamic Dynamic Logic
    In Marcus Kracht, Maarten de Rijke, Heinrich Wansing & Michael Zakharyaschev (eds.), Advances in Modal Logic, Csli Publications. pp. 239-260. 2012.
  • Logic, Rationality, and Interaction. LORI 2017. Lecture Notes in Computer Science, vol 10455. (edited book)
    with Alexandru Baltag and Tomoyuki Yamada
    Springer. 2017.
  • What Are Hybrid Languages?
    In Marcus Kracht, Maarten de Rijke, Heinrich Wansing & Michael Zakharyaschev (eds.), Advances in Modal Logic, Csli Publications. pp. 41-62. 1998.
  • What Are Hybrid Languages?
    In Marcus Kracht, Maarten de Rijke, Heinrich Wansing & Michael Zakharyaschev (eds.), Advances in Modal Logic, Volume 1, Csli Publications. pp. 41-62. 1998.