Notre Dame Journal of Formal Logic

Worlds and Times

Ulrich Meyer


There are many parallels between the role of possible worlds in modal logic and that of times in tense logic. But the similarities only go so far, and it is important to note where the two come apart. This paper argues that even though worlds and times play similar roles in the model theories of modal and tense logic, there is no tense analogue of the possible-worlds analysis of modal operators. An important corollary of this result is that presentism cannot be the tense analogue of actualism.

Article information

Notre Dame J. Formal Logic Volume 47, Number 1 (2006), 25-37.

First available: 27 March 2006

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Mathematical Reviews number (MathSciNet)

Zentralblatt MATH identifier

Primary: 03B44: Temporal logic 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}
Secondary: 03C80: Logic with extra quantifiers and operators [See also 03B42, 03B44, 03B45, 03B48]

tense logic modal logic times possible worlds actuality operator presentism actualism


Meyer, Ulrich. Worlds and Times. Notre Dame Journal of Formal Logic 47 (2006), no. 1, 25--37. doi:10.1305/ndjfl/1143468309.

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