Notre Dame Journal of Formal Logic

Logics of Relative Identity

Paweł Garbacz


This paper is the first part of an exploration into the logical properties of relative identity. After providing the semantic grounds for various monadic logics of relative identity, I define the minimal system and its nine extensions. It is suggested that despite their purely formal origin at least some of them may contain nontrivial philosophical insights. All logics are axiomatized by means of sound and complete sequent calculi. I show their affinities with existing formalizations.

Article information

Notre Dame J. Formal Logic, Volume 43, Number 1 (2002), 27-50.

First available in Project Euclid: 15 December 2003

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Mathematical Reviews number (MathSciNet)

Zentralblatt MATH identifier

Primary: 03B60: Other nonclassical logic
Secondary: 03B80: Other applications of logic

relative identity indiscernibility


Garbacz, Paweł. Logics of Relative Identity. Notre Dame J. Formal Logic 43 (2002), no. 1, 27--50. doi:10.1305/ndjfl/1071505768.

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