Inconsistency handling in multi-perspective specifications

The development of most large and complex systems necessarily involves many people - each with their own perspectives on the system defined by their knowledge, responsibilities, and commitments. To address this we have advocated distributed development of specifications from multiple perspectives. However, this leads to problems of identifying and handling inconsistencies between such perspectives. Maintaining absolute consistency is not always possible. Often this is not even desirable since this can unnecessarily constrain the development process, and can lead to the loss of important information. Indeed since the real-world forces us to work with inconsistencies, we should formalise some of the usually informal or extra-logical ways of responding to them. This is not necessarily done by eradicating inconsistencies but rather by supplying logical rules specifying how we should act on them. To achieve this, we combine two lines of existing research: the Viewpoints framework for perspective development, interaction and organisation, and a logic-based approach to inconsistency handling. This paper presents our technique for inconsistency handling in the ViewPoints framework by using simple examples.