Computing with words in formal methods

Formal methods are used to improve the quality of complex computer software by means of documenting system specifications in a precise and structured manner, the most popular specification language for formal methods is Z. Ho wever, based on classical set theory and classical logic, this mathematical language can only deal effectively with well-defined problems. This is a d isadvantage that classical set operators and classical predicate logic can offer to formal methods. In this paper, the theory of fuzzy information gra nulation is discussed with an attempt to build toward flexible formal softw are specifications in which many aspects of human reasoning and natural lan guage can be effectively addressed in mathematical terms. In other words, t he tolerance of imprecision necessarily required in many real-life software systems can be represented in the clear and structured mathematics of the fuzzy information granulation theory within the extended framework of forma l methods. (C) 2000 John Wiley & Sons, Inc.