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    Carmelics

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    Halpern — Carmelics
    Thinkers/Halpern
    Halpern

    Halpern

    contemporaryEpistemic Logic, Formal Methods, Analytic Philosophy

    b. 1953

    Joseph Y. Halpern is a computer scientist and logician at Cornell University whose work bridges formal epistemology, game theory, and the logic of knowledge in distributed systems. He is best known for foundational contributions to epistemic logic, plausibility-based reasoning, and the formal analysis of causality. His research engages directly with debates in game theory concerning common knowledge, rationality, and the semantics of belief revision.

    WWikipedia

    Notable Achievements

    1

    Co-authored 'Reasoning About Knowledge' (1995), a foundational text in formal epistemic logic

    2

    Developed the Halpern-Pearl (HP) account of actual causality using structural causal models

    3

    Introduced plausibility measures as a unified generalization of probability and possibility theory

    4

    Analyzed the logical and computational complexity of reasoning about knowledge and common knowledge

    5

    Clarified foundational disputes in game theory (e.g., Aumann vs. Stalnaker) through precise modal-logical modeling

    Positions & Arguments(3)

    Skepticism

    claim

    The difference in conclusions between Aumann (1995) and Stalnaker (1998) is due to differing models of belief revision upon deviation from the backward induction path

    claim

    Plausibility updates in sequential games during actual play differ in interpretation from plausibility updates used in pregame deliberation for Backward Induction.

    claim

    There is a fundamental tension between treating logical knowledge as a priori and the computational intractability of deciding logical validity.

    Truth & Knowledge

    claim

    The difference in conclusions between Aumann (1995) and Stalnaker (1998) is due to differing models of belief revision upon deviation from the backward induction path

    claim

    Plausibility updates in sequential games during actual play differ in interpretation from plausibility updates used in pregame deliberation for Backward Induction.

    claim

    There is a fundamental tension between treating logical knowledge as a priori and the computational intractability of deciding logical validity.

    At a Glance

    Ideas

    3

    Topics

    2

    Era

    contemporary

    Tradition

    Epistemic Logic, Formal Methods, Analytic Philosophy

    Topic Influence

    Truth & Knowledge3
    Skepticism3

    Related Thinkers

    David Lewis2 sharedImmanuel Kant2 sharedBoyd2 sharedBrian Skyrms2 sharedStathis Psillos2 sharedBertrand Russell2 sharedDavid Hume2 sharedAristotle2 shared

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