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Unawareness with �possible� possible worlds


  • Oliver Walker


Logical structures for modeling agents� reasoning about unawareness are presented where it can hold simultaneously that: (i) agents� beliefs about whether they are fully aware need not be veracious with partitional information; and (ii) the agent is fully aware if and only if she is aware of a fixed domain of formulae. In light of (ii), all states are deemed �possible�. Semantics operate in two stages, with belief in the second stage determined by truth in the first stage. Characterization theorems show that, without the first stage, the structures validate the same conditions as those of Halpern and Rego (2009a).

Suggested Citation

  • Oliver Walker, 2011. "Unawareness with �possible� possible worlds," GRI Working Papers 69, Grantham Research Institute on Climate Change and the Environment.
  • Handle: RePEc:lsg:lsgwps:wp69

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    References listed on IDEAS

    1. Simon Grant & John Quiggin, 2013. "Inductive reasoning about unawareness," Economic Theory, Springer;Society for the Advancement of Economic Theory (SAET), vol. 54(3), pages 717-755, November.
    2. Kim-Sau Chung & Oliver Board, 2007. "Object-Based Unawareness," Working Papers 2007-2, University of Minnesota, Department of Economics, revised 24 Aug 2007.
    3. Burkhard C. Schipper & Oliver Board & Kim-Sau Chung, 2009. "Two Models of Unawareness: Comparing the object-based and subjective-state-space approaches," Working Papers 93, University of California, Davis, Department of Economics.
    4. Heifetz, Aviad & Meier, Martin & Schipper, Burkhard C., 2006. "Interactive unawareness," Journal of Economic Theory, Elsevier, vol. 130(1), pages 78-94, September.
    5. Modica, Salvatore & Rustichini, Aldo, 1999. "Unawareness and Partitional Information Structures," Games and Economic Behavior, Elsevier, vol. 27(2), pages 265-298, May.
    6. Edi Karni & Marie-Louise Vier?, 2013. ""Reverse Bayesianism": A Choice-Based Theory of Growing Awareness," American Economic Review, American Economic Association, vol. 103(7), pages 2790-2810, December.
    7. Heinsalu, Sander, 2012. "Equivalence of the information structure with unawareness to the logic of awareness," Journal of Economic Theory, Elsevier, vol. 147(6), pages 2453-2468.
    8. Halpern, Joseph Y., 2001. "Alternative Semantics for Unawareness," Games and Economic Behavior, Elsevier, vol. 37(2), pages 321-339, November.
    9. repec:pit:wpaper:379 is not listed on IDEAS
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    Cited by:

    1. Halpern, Joseph Y. & Rêgo, Leandro C., 2013. "Reasoning about knowledge of unawareness revisited," Mathematical Social Sciences, Elsevier, vol. 65(2), pages 73-84.

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