A Knowledge-based System for Translating FOL Formulas into NL Sentences

  • Aikaterini Mpagouli
  • Ioannis Hatzilygeroudis
Part of the IFIP International Federation for Information Processing book series (IFIPAICT, volume 296)


In this paper, we present a system that translates first order logic (FOL) formulas into natural language (NL) sentences. The motivation comes from an intelligent tutoring system teaching logic as a knowledge representation language, where it is used as a means for feedback to the users. FOL to NL conversion is achieved by using a rule-based approach, where we exploit the pattern matching capabilities of rules. So, the system consists of a rule-based component and a lexicon. The rule-based unit implements the conversion process, which is based on a linguistic analysis of a FOL sentence, and the lexicon provides lexical and grammatical information that helps in producing the NL sentences. The whole system is implemented in Jess, a java-based expert system shell. The conversion process currently covers a restricted set of FOL formulas.


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Copyright information

© IFIP International Federation for Information Processing 2009

Authors and Affiliations

  • Aikaterini Mpagouli
    • 1
  • Ioannis Hatzilygeroudis
    • 1
  1. 1.Department of Computer Engineering & InformaticsUniversity of Patras, School of EngineeringPatrasHellas

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