Journal of Computer Science and Technology

, Volume 14, Issue 2, pp 159–164 | Cite as

A general scheme for formalizing defaults using the predicateab(I, S)



In common sense reasoning two typical types of defaults are encountered. One is of the form “All birds can fly exceptb 1,b 2,…, andb m (m≥1)”, and the other “All birds can fly, but there exist exceptions”. The first type of defaults is readily formalized but the other, as some researchers have noticed, is difficult to deal with. This paper establishes a general scheme for formalizing defaults of the two types, the key to which is the introduction of a two-argument predicateab(I, S) to represent exceptional object.


common sense reasoning default formalization 


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Copyright information

© Science Press, Beijing China and Allerton Press Inc. 1999

Authors and Affiliations

  1. 1.Department of Computer ScienceChongging UniversityChongqingP.R. China

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