A Diagrammatic Inference System with Euler Circles

Koji Mineshima, Mitsuhiro Okada, Ryo Takemura

Research output: Contribution to journalArticlepeer-review

24 Citations (Scopus)


Proof-theory has traditionally been developed based on linguistic (symbolic) representations of logical proofs. Recently, however, logical reasoning based on diagrammatic or graphical representations has been investigated by logicians. Euler diagrams were introduced in the eighteenth century. But it is quite recent (more precisely, in the 1990s) that logicians started to study them from a formal logical viewpoint. We propose a novel approach to the formalization of Euler diagrammatic reasoning, in which diagrams are defined not in terms of regions as in the standard approach, but in terms of topological relations between diagrammatic objects. We formalize the unification rule, which plays a central role in Euler diagrammatic reasoning, in a style of natural deduction. We prove the soundness and completeness theorems with respect to a formal set-theoretical semantics. We also investigate structure of diagrammatic proofs and prove a normal form theorem.

Original languageEnglish
Pages (from-to)365-391
Number of pages27
JournalJournal of Logic, Language and Information
Issue number3
Publication statusPublished - 2012 Jul


  • Diagrammatic reasoning
  • Euler diagram
  • Proof-theory

ASJC Scopus subject areas

  • Computer Science (miscellaneous)
  • Philosophy
  • Linguistics and Language


Dive into the research topics of 'A Diagrammatic Inference System with Euler Circles'. Together they form a unique fingerprint.

Cite this