A General Scheme for Formalizing Defaults Using the Predicate ab(I,S)  

作　　者：沈一栋 

出　　处：《Journal of Computer Science & Technology》1999年第2期159-164,共6页计算机科学技术学报（英文版）

摘　　要：In common sense reasoning two typical types of defaults are encoun- tered. One is of the form 'All birds can fly except b1, b2,…, and bm(m>1)' , and the other 'All birds can fly, but there exist exceptiona' . The first type of defaults is readily formalized but the other, as some researchers have noticed, is difficult to deal witb. This paper establisbes a geaeral scheme for formalising defaults of the two typea, the key to which is the introduction of a two-argument predicate ab(I,S) to represent exceptional objects.In common sense reasoning two typical types of defaults are encoun- tered. One is of the form 'All birds can fly except b1, b2,…, and bm(m>1)' , and the other 'All birds can fly, but there exist exceptiona' . The first type of defaults is readily formalized but the other, as some researchers have noticed, is difficult to deal witb. This paper establisbes a geaeral scheme for formalising defaults of the two typea, the key to which is the introduction of a two-argument predicate ab(I,S) to represent exceptional objects.

关 键 词：common sense reasoning DEFAULT FORMALIZATION 

分 类 号：TP338.6[自动化与计算机技术—计算机系统结构]