Expanding SNePS capabilities with LORE

  • Nuno J. Mamede
  • João P. Martins
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 437)


We briefly describe LORE, a logic with four values, the traditional truth values T and F, and two “Unknown” values, allowing to differentiate between knowing that nothing is known, and not knowing (with the available resources) whether it is known. A computer system based on LORE has the capability to remember all the paths followed during an attempt to answer a question. For each path, it records the used hypotheses (the hypotheses that constitute the path), the missing hypotheses (when the path did not lead to an answer), and why they were assumed missing. A number of examples of the use of LORE are discussed, and it is shown that SNePS capabilities can be expanded if LORE is accepted as the logic underlying its inferences.


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Copyright information

© Springer-Verlag Berlin Heidelberg 1990

Authors and Affiliations

  • Nuno J. Mamede
    • 1
  • João P. Martins
    • 1
  1. 1.Instituto Superior TécnicoTechnical University of LisbonLisboaPortugal

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