Journal of Philosophical Logic

, Volume 29, Issue 4, pp 383–408 | Cite as

Input/Output Logics

  • David Makinson
  • Leendert van der Torre


In a range of contexts, one comes across processes resembling inference, but where input propositions are not in general included among outputs, and the operation is not in any way reversible. Examples arise in contexts of conditional obligations, goals, ideals, preferences, actions, and beliefs. Our purpose is to develop a theory of such input/output operations. Four are singled out: simple-minded, basic (making intelligent use of disjunctive inputs), simple-minded reusable (in which outputs may be recycled as inputs), and basic reusable. They are defined semantically and characterised by derivation rules, as well as in terms of relabeling procedures and modal operators. Their behaviour is studied on both semantic and syntactic levels.

input/output logic reusability identity conditional goals conditional obligations deontic logic 


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Copyright information

© Kluwer Academic Publishers 2000

Authors and Affiliations

  • David Makinson
    • 1
  • Leendert van der Torre
    • 2
  1. 1.Department of ComputingKing"s College LondonVille d"AvrayFrance
  2. 2.Department of Artificial IntelligenceVrije Universiteit AmsterdamAmsterdamthe Netherlands

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