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Publications (selected)

Monographs

• The Logic of Precedent: Constraint, Freedom, and Common Law Reasoning Cambridge University Press (in press)
• Reasons as Defaults. Oxford University Press (2012), xvi+259pp
• Frege on Definitions: A Case Study of Semantic Content. Oxford University Press (2007; paperback, 2009), xiv+176 pp.
  
• Agency and Deontic Logic. Oxford University Press (2001; paperback, 2008), xiii+192 pp.

Edited collections

• Handbook of Deontic Logic and Normative Systems, Volume 2 (Dov Gabbay, John Horty, Xavier Parent, Ron van der Meyden, and Leendert van der Torre, eds). College Publications (2021), ix+790pp.
• JPL 40: The Fortieth Anniversary Issue (John Horty and Frank Veltman, eds). Special Issue of the Journal of Philosophical Logic (2015)
• Handbook of Deontic Logic and Normative Systems (Dov Gabbay, John Horty, Xavier Parent, Ron van der Meyden, and Leendert van der Torre, eds). College Publications (2013), ix+634pp.
• Logic, Rationality, and Interaction: Proceedings of the Second International Workshop (Xiangdong He, John Horty, and Eric Pacuit, eds). Springer Lecture Notes in Computer Science, vol. 5834, Springer (2009), xi+329 pp.

Articles

• Precedent and open texture. Forthcoming in Oxford Studies in Philosophy of Law, volume 5, Leslie Green and Brian Leiter (eds), Oxford University Press.
• A contrario argument and default reasoning. In New Conversations in Philosophy, Law, and Politics, Ruth Chang and Amia Srinivasan (eds), Oxford University Press (2024), pp. 580 - 591.
• The importance of intermediate factors (Ilaria Canavotto and John Horty). In Proceedings of the Thirty sixth International Conference on Legal Knowledge and Information Systems (JURIX 2023), IOS Press (2023), pp. 13 - 22.
• Reasoning with hierarchies of open-textured predicates (Ilaria Canavotto and John Horty). In Proceedings of the Ninteenth International Conference on Artificial Intelligence and Law (ICAIL 2023), Association for Computing Machinery Press (2023), pp. 52 - 61.
• How does precedent constrain? In The Philosophical Foundations of Precedent, Timothy Endicott, Hafsteinn Kristjansson, and Sebastian Lewis (eds.), Oxford University Press (2023), pp. 185 - 197.
• Grant Lamond's account of precedent: a personal encounter. In New Essays on the Nature of Legal Reasoning, Mark McBride and James Penner(eds), Hart Publishing Company (2022), pp. 139 - 160.
• Piecemeal knowledge acquisition for computational normative reasoning (Ilaria Canavotto and John Horty). In Proceedings of the 2022 AAAI/ACM Conference on AI, Ethics, and Society (AIES’22), ACM Press (2022), pp. 171 - 180.
• Modifying the reason model. Artificial Intelligence and Law, vol. 29 (2021), pp. 271 - 285.
• Reasoning with dimensions and magnitudes. Artificial Intelligence and Law, vol. 27 (2019), pp. 309 - 345.
• Epistemic oughts in stit semantics. Ergo, vol. 6 (2019), pp. 71 - 120.
• The logic of reasons (Shyam Nair and John Horty). In The Oxford Handbook of Reasons and Normativity, Danial Star (ed.), Oxford University Press (2018), pp. 67 - 84.
• Action types in stit semantics (John Horty and Eric Pacuit). Review of Symbolic Logic, vol. 10 (2017), pp. 17 - 37.
• Reasoning with dimensions and magnitudes. In Proceedings of the Sixteenth International Conference on Artificial Intelligence and Law (ICAIL 2017), Association for Computing Machinery Press (2017), pp. 109 - 118.
  
  *** Winner of Carole Hafner Best Paper Award, ICAIL 2017.
  
• Reasoning with precedents as constrained natural reasoning. In Weighing Reasons, Errol Lord and Barry Maguire (eds.), Oxford University Press (2016), pp. 193-212.
• Constraint and freedom in the common law. Philosophers' Imprint, vol. 15, no. 25 (2015), 27 pp.
• Requirements, oughts, intentions. Philosophy and Phenomenological Research (Book symposium contribution on John Broome's Rationality through Reasoning), vol. 91 (2015), pp. 220 - 229.
• Deontic modals: Why abandon the classical semantics? Pacific Philosophical Quarterly (Special Issue on Deontic Modality, Stephen Finlay and Mark Schroeder, eds.), vol. 95 (2014), pp. 424 - 460.
• Norm change in the common law. In David Makinson on Classical Methods for Nonclassical Problems, Sven Ove Hansson (ed.), Springer (2014), pp. 335 - 355.
• Stit logics, games, knowledge, and freedom (Roberto Ciuni and John Horty). In Johan van Benthem on Logical and Informational Dynamics, Alexandru Baltag and Sonja Smets (eds.), Springer (2014), pp. 631 - 656.
• An appreciation of John Pollock's work on the computational study of argument (Henry Prakken and John Horty). Argumentation and Computation, vol. 3 (2012), pp. 1 - 19.
• A factor-based definition of precedential constraint (John Horty and Trevor Bench-Capon). Artificial Intelligence and Law , vol. 20 (2012), pp. 181-214.
• Rules and reasons in the theory of precedent. Legal Theory, vol. 17 (2011), pp. 1 - 33.
  
  *** Reprinted in The Philosopher's Annual, vol. 31 ("Ten best papers of 2011").
  
• Reasons and precedent. In Proceedings of the Thirteenth International Conference on Artificial Intelligence and Law (ICAIL-2011), Association for Computing Machinery Press (2011), pp. 41 - 50.
• Perspectival act utilitarianism. In Dynamic Formal Epistemology, Patrick Girard, Mathieu Marion, and Olivier Roy (eds.), Synthese Library, vol. 351, Springer (2011), pp. 197 - 222.
• Reasons as defaults. Philosophers' Imprint, vol. 7 no. 3 (2007), 28 pp.
  
  Abbreviated version translated as Grunde als Defaults in Welt der Grunde: Beitrge zu den Kolloquium des XXII Deutschen Kongresses fur Philosophie, Julian Nida-Rumelin and Elif Ozmen (eds.), Felix Meiner Verlag Hamburg, to appear in fall 2012.
• Defaults with priorities. Journal of Philosophical Logic, vol. 36 (2007), pp. 367 - 413.
• Double time reference in the evaluations of actions. In Modality Matters: Twenty-five Essays in Honour of Krister Segerberg, Henrik Lagerlund, Sten Lindstrom, and Ryszard Sliwinski (eds.), Uppsala Philosophical Studies, vol 53, Uppsala University Press (2006).
• The result model of precedent. Legal Theory, vol. 10 (2004), pp. 19 - 31.
• Reasoning with moral conflicts. Nous, vol. 37 (2003), pp. 557 - 605.
• Skepticism and floating conclusions. Artificial Intelligence, vol. 135 (2002), pp. 55 - 72.
  
  A preliminary version appears in Working Notes of Common Sense 2001: The Fifth International Symposium on Logical Formalizations of Commonsense Reasoning , Ernest Davis, John McCarthy, Leora Morgenstern, and Raymond Reiter (eds.), Courant Institute of Mathematical Sciences, New York University (2001), pp. 156 - 167.
• Review of Sven Ove Hansson, The Structure of Values and Norms. Notre Dame Philosophical Reviews , June 2002.
• Evaluating new options in the context of existing plans (John Horty and Martha Pollack). Artificial Intelligence, vol. 127 (2001), pp. 199 - 220.
• Argument construction and reinstatement in logics for defeasible reasoning. Artificial Intelligence and Law, vol. 9 (2001), pp. 1 - 28.
• Nonmonotonic Logic. In The Blackwell Guide to Philosophical Logic, Lou Goble (ed.), Blackwell Publishers (2001), pp. 336 - 361.
• Merging plans with quantitative temporal constraints, temporally extended actions, and conditional branches (Ioannis Tsamardinos, Martha Pollack, and John Horty). In Proceedings of the Fifth International Conference on Artificial Intelligence Planning and Scheduling (AIPS-2000), American Association for Artificial Intelligence Press, pp. 264 - 272.
  
  *** Winner of Best Student Paper Award, AIPS-2000.
  
• There's more to life than making plans: plan management in dynamic, multi-agent environments (Martha Pollack and John Horty). AI Magazine, vol. 20 (1999), pp. 71 - 84.
• Precedent, deontic logic, and inheritance. In Proceedings of the Seventh International Conference on Artificial Intelligence and Law (ICAIL-99), Association for Computing Machinery Press (1999), pp. 63 - 72.
• Adjustable autonomy for a plan management agent (Martha Pollack, Ioannis Tsamardinos, and John Horty). In Proceedings of the AAAI Spring Symposium on Adjustable Autonomy, American Association for Artificial Intelligence Press (1999).
• Plan management issues for cognitive robotics (Martha Pollack and John Horty). In Proceedings of the AAAI Fall Symposium on Cognitive Robotics, Chitta Baral, Kurt Konolige, Gerhard Lakemayer, Raymond Reiter, and Murry Shanahan (eds.), American Association for Artificial Intelligence Press (1998), pp. 76 - 83.
• A unifying algorithm for conditional and probabilistic planning (Nilufer Onder, Martha Pollack, and John Horty). In Proceedings of the AIPS'98 Workshop on Integrating Planning, Scheduling and Execution in Dynamic and Uncertain Environments, A. Kott (ed.), American Association for Artificial Intelligence Press (1998), pp. 106 - 112.
• Nonmonotonic foundations for deontic logic. In Defeasible Deontic Logic, Donald Nute (ed.), Kluwer Academic Publishers (1997), pp. 17 - 44.
• Agency and obligation . Synthese, vol. 108 (1996), pp. 269 - 307.
  
  A preliminary version appears in Deontic Logic, Agency, and Normative Systems: Proceedings of the Third International Workshop on Deontic Logic in Computer Science, Mark Brown and Jose Carmo (eds.), Workshops in Computing Series, Springer Verlag (1996), pp. 98 - 122.
• Nondeterminism and dominance: foundations of planning and qualitative decision theory (Richmond Thomason and John Horty). In Proceedings of the Sixth Conference on Theoretical Aspects of Rationality and Knowledge (TARK-96), Yoav Shoham (ed.), Morgan-Kaufmann Publishing Company (1996), pp. 229 - 250.
• The deliberative stit: a study onf action, omission, ability, and obligation (John Horty and Nuel Belnap). Journal of Philosophical Logic, vol. 24 (1995), pp. 583 - 644.
  
  *** Reprinted in The Philosopher's Annual, vol. 18 ("Ten best papers of1995").
  
  Portions revised and reprinted in Facing the Future: Agents and Choices in Our Indeterministic World, by Nuel Belnap, Michael Perloff, and Ming Xu, Oxford University Press (2001).
• Moral dilemmas and nonmonotonic logic. Journal of Philosophical Logic, vol. 23 (1994), pp. 35 - 65.
  
  A preliminary version appears in Proceedings of the First International Workshop on Deontic Logic in Computer Science, John-Jules Charles Meyer and Roel Wieringa (eds.), Free University of Amsterdam (1991), pp. 212 - 231.
• Some direct theories of nonmonotonic inheritance. In Handbook of Logic in Artificial Intelligence and Logic Programming, Volume 3: Nonmonotonic Reasoning and Uncertain Reasoning, Dov Gabbay, Christopher Hogger, and John Robinson (eds.), Oxford University Press (1994), pp. 111 - 187.
• Frege on the psychological significance of definitions. Philosophical Studies (Special Issue on Definitions), vol. 69 (1993), pp.113 - 153.
• View updates in stratified disjunctive databases (John Grant, John Horty, Jorge Lobo, and Jack Minker). Journal of Automated Reasoning, vol. 11 (1993), pp. 249 - 267.
• Deontic logic as founded on nonmonotonic logic. Annals of Mathematics and Artificial Intelligence (Special Issue on Deontic Logic in Computer Science), vol. 9 (1993), pp. 69 - 91.
  
  A preliminary version appears in Proceedings of the Second Symposium on Logical Formalizations of Commonsense Reasoning , Vladimir Lifschitz, John McCarthy, Leora Morgenstern, and Yoav Shoham (eds.), American Association for Artificial Intelligence Press (1993).
• Reasoning about ignorance: a note on the Bush-Gorbachev problem. (Sarit Kraus, Donald Perlis, and John Horty) Fundamenta Informaticae (Special Issue on Logics for Artificial Intelligence), vol. 15 (1991), pp. 325 - 332.
• Conditionals and artificial intelligence (John Horty and Richmond Thomason). Fundamenta Informaticae (Special Issue on Logics for Artificial Intelligence), vol. 15 (1991), pp. 301 - 323.
• A credulous theory of mixed inheritance. In Inheritance Hierarchies in Knowledge Representation and Programming Languages , M. Lenzerini, Daniele Nardi, and Maria Simi (eds.), John Wiley and Sons Press (1991), pp. 13 - 28.
• A skeptic's menagerie: conflictors, preemptors, reinstaters, and zombies in nonmonotonic inheritance (David Touretzky, Richmond Thomason, and John Horty). In Proceedings of the Twelfth International Joint Conference on Artificial Intelligence (IJCAI-91), Morgan Kaufmann Publishers (1991), pp. 478 - 483.
• A skeptical theory of inheritance in nonmonotonic semantic networks (John Horty, Richmond Thomason, and David Touretzky). Artificial Intelligence, vol. 42 (1990), pp. 311 - 348.
  
  An extended version including LISP code appears as Technical Report CMU-CS-87-175, Computer Science Department, Carnegie Mellon University (1987), 62 pp.
• A skeptical theory of mixed inheritance. In Truth or Consequences: Essays in Honor of Nuel Belnap, Jon Michael Dunn and Anil Gupta (eds.), Kluwer Academic Publishers (1990), pp. 267 - 281.
• Boolean extensions of inheritance networks (John Horty and Richmond Thomason). In Proceedings of the Eighth National Conference on Artificial Intelligence (AAAI-90), The MIT Press (1990), pp. 633 - 639.
• Logics for inheritance theory (Richmond Thomason and John Horty). In Proceedings of the Second International Workshop on Nonmonotonic Reasoning, Michael Reinfrank, Johan de Kleer, Matthew Ginsberg, and Eric Sandewall (eds.), Springer Verlag Lecture Notes in Artificial Intelligence, vol. 346, Springer Verlag (1989), pp. 220 - 237.
• Mixing strict and defeasible inheritance (John Horty and Richmond Thomason). In Proceedings of the Seventh National Conference on Artificial Intelligence (AAAI-88), Morgan Kaufmann Publishers (1988), pp. 427 - 432.
• A skeptical theory of inheritance in nonmonotonic semantic networks (preliminary version) (John Horty, Richmond Thomason, and David Touretzky). In Proceedings of the Sixth National Conference on Artificial Intelligence (AAAI-87), Morgan Kaufmann Publishers (1987), pp. 358 - 363.
  
  *** Honorable mention, Best Paper Award, AAAI-87.
  
• A clash of intuitions: the current state of nonmonotonic multiple inheritance systems (David Touretzky, John Horty, and Richmond Thomason). In Proceedings of the Tenth International Joint Conference on Artificial Intelligence (IJCAI-87), Morgan Kaufmann Publishers (1987), pp. 476 - 482.
• A calculus for inheritance in monotonic semantic nets (Richmond Thomason, John Horty, and David Touretzky). In Proceedings of the Second International Symposium on Methodologies for Intelligent Systems, North-Holland Publishing Company (1987), pp. 280 - 287.
  
  An extended version appears as Technical Report CMU-CS-86-138, Computer Science Department, Carnegie Mellon University (1986), 24 pp.

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