, Volume 69, Issue 3, pp 363–376 | Cite as

Wittgensteinian Tableaux, Identity, and Co-Denotation

  • Kai F. Wehmeier
Original Article


Wittgensteinian predicate logic (W-logic) is characterized by the requirement that the objects mentioned within the scope of a quantifier be excluded from the range of the associated bound variable. I present a sound and complete tableaux calculus for this logic and discuss issues of translatability between Wittgensteinian and standard predicate logic in languages with and without individual constants. A metalinguistic co-denotation predicate, akin to Frege’s triple bar of the Begriffsschrift, is introduced and used to bestow the full expressive power of first-order logic with identity on W-logic in the presence of constants.


Predicate Symbol Sequent Calculus Individual Constant Open Branch Existential Sentence 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



Thanks to Sam Hillier for various discussions concerning W-logic, and to Peter Schroeder-Heister for the suggestion to provide tableaux rules for W-logic. I also wish to acknowledge my gratitude to Ulrich Pardey for numerous illuminating discussions regarding identity. Finally, I am grateful to two anonymous referees for this journal for asking a number of technical and philosophical questions that helped improve this paper.


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Copyright information

© Springer Science+Business Media B.V. 2008

Authors and Affiliations

  1. 1.Logic & Philosophy of ScienceUniversity of CaliforniaIrvineUSA

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