A strengthening of rational closure in DLs: reasoning about multiple aspects
This work addresses a foundational issue in knowledge representation for AI, specifically in handling exceptions and multiple aspects in typicality reasoning, but it appears incremental as it builds on prior extensions.
The paper tackles the problem of representing typicality with exceptions in Description Logics by strengthening an existing extension with a typicality operator to enable separate reasoning about multiple aspects, such as flying and having nice feathers, allowing inheritance of non-exceptional properties.
We propose a logical analysis of the concept of typicality, central in human cognition (Rosch,1978). We start from a previously proposed extension of the basic Description Logic ALC (a computationally tractable fragment of First Order Logic, used to represent concept inclusions and ontologies) with a typicality operator T that allows to consistently represent the attribution to classes of individuals of properties with exceptions (as in the classic example (i) typical birds fly, (ii) penguins are birds but (iii) typical penguins don't fly). We then strengthen this extension in order to separately reason about the typicality with respect to different aspects (e.g., flying, having nice feather: in the previous example, penguins may not inherit the property of flying, for which they are exceptional, but can nonetheless inherit other properties, such as having nice feather).