摘要:

In the literature on Non-Monotonic Logics, many examples of defeasible deductions infer that an arbitrarily chosen individual in a given set has the properties that we consider as “typical” for the elements of that set. In the paper we provide a logical framework, based on first-order logic, suitable for this kind of inferences. The main features of our approach are: 1) typicality of a given property for the individuals in a given set is represented by means of a binary determiner, 2) individual constants are evaluated on sets of individuals, so that a “range of uncertainty” is ascribed to them, 3) the adopted formalism and semantics allow formulas that adequately represent assertions like “it is highly plausible that the individual c has the property P”, and 4) the formal conditions under which “c has the property P” can consistently be inferred from the above assertion are determined, 5) non-monotonicity is achieved by changing the evaluation of the individual constants. In Appendices A, B and C, we provide a sound complete axiom system for the logic considered in the paper.

ISSN:1166-3081    

DOI:10.1080/11663081.1996.10510883

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor

摘要:

The paper continues the theme of [KM 93]. We differentiate between our approach to knowledge representation and that of others by expressing the following Working Hypothesis: Knowledge is a data type, and knowledge revision is accomplished by continuous operations on it, which are coordinated with its effective basis. Staying in the limits of Belnap's paradigm of the admittance of contradictory information into the computer's memory, our purpose in this paper is to reduce as much as possible all the computable processes needed for modifing the current state of computer's knowledge and describe conditions for possible maneuvering. In particular, we solve some problems of decidability concerning operations on the minimal states, which are regarded as natural knowledge transformers. We show, also, how to express those operations in lattice theory terms that leads to the simplification of their computation on the lattice of minimal states. The problem of backtracking in the presented context is considered as well.

ISSN:1166-3081    

DOI:10.1080/11663081.1996.10510884

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor

ISSN:1166-3081    

DOI:10.1080/11663081.1996.10510885

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor

ISSN:1166-3081    

DOI:10.1080/11663081.1996.10510886

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor

ISSN:1166-3081    

DOI:10.1080/11663081.1996.10510888

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor

ISSN:1166-3081    

DOI:10.1080/11663081.1996.10510882

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor