Notre Dame Journal of Formal Logic

Information and Impossibilities

Jon Barwise


In this paper I explore informationalism, a pragmatic theory of modality that seems to solve some serious problems in the familiar possible worlds accounts of modality. I view the theory as an elaboration of Stalnaker's moderate modal realism, though it also derives from Dretske's semantic theory of information. Informationalism is presented in Section 2 after the prerequisite stage setting in Section 1. Some applications are sketched in Section 3. Finally, a mathematical model of the theory is developed in Section 4.

How many times have I said to you that when you have eliminated the impossible, whatever remains, however improbable, must be the truth? (Arthur Conan Doyle)

You've put me in an impossible situation. (Anonymous)

[N]othing we imagine is absolutely impossible. (David Hume)

Article information

Notre Dame J. Formal Logic, Volume 38, Number 4 (1997), 488-515.

First available in Project Euclid: 10 December 2002

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Mathematical Reviews number (MathSciNet)

Zentralblatt MATH identifier

Primary: 03A05: Philosophical and critical {For philosophy of mathematics, see also 00A30}
Secondary: 03B45: Modal logic (including the logic of norms) {For knowledge and belief, see 03B42; for temporal logic, see 03B44; for provability logic, see also 03F45}


Barwise, Jon. Information and Impossibilities. Notre Dame J. Formal Logic 38 (1997), no. 4, 488--515. doi:10.1305/ndjfl/1039540766.

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