Artificial Intelligence (AI) has, as one of its central topics, the ability to represent and reason with common sense knowledge. Early forays into common sense reasoning about the physical world involved solving textbook problems on physics and mathematics. These were not adequate for reasoning about most commonplace physical scenarios. A system suggested by DeKleer, involving both quantitative knowledge and qualitative information concerning the physical situation marked the starting point for qualitative physics (Weld & DeKleer, 1990). Hayes’ Naive Physics Manifesto (Hayes, 1985) paved the way for establishing qualitative physics (meantime re-christened qualitative reasoning) as an important topic of research within AI. Qualitative Reasoning (QR) is an approach for dealing with common sense knowledge without recourse to complete quantitative knowledge. Representation of knowledge is through a limited repository of qualitative abstractions. Space and spatial change is an important part of common sense reasoning. Naive Physics Manifesto proposed to represent space-time with four-dimensional histories. Despite early forays such as the Naive Physics Manifesto, representation of space within QR has been ill addressed. Nevertheless, there has been an increasing interest over the last few years in qualitative spatial reasoning - reasoning about space using qualitative abstractions.
Qualitative Spatial Reasoning
Within QSR, qualitative spatial representations addressing different aspects of space including topology, orientation, shape, size, and distance have been put forward.
Key Terms in this Chapter
Qualitative Spatial Reasoning: Qualitative Spatial Reasoning is concerned with providing calculus which allow a machine to represent and reason with spatial entities without resort to traditional quantitative techniques. Representation is concerned with different forms of spatial knowledge and reasoning is concerned with methods and techniques for decision-making. The term Qualitative Spatial Reasoning subsumes both the sub-fields of representation and reasoning.
Mereotopology: Topological notions have to be added to mereology to provide an adequate qualitative theory of space. Such combination of the disciplines of mereology and topology is referred to as mereotopology.
Region Connection Calculus: RCC is a mereotopological theory of space. The topological primitive of connection is primal from which the mereological primitive of parthood is defined. The theory has a set of eight jointly exhaustive and pair-wise disjoint base relations referred to as RCC-8.
Spatio-Temporal History: Space-time regions traced by objects over time are termed space-time history or spatio-temporal history.
Qualitative Reasoning: Approach for dealing with common-sense knowledge without recourse to complete quantitative knowledge. Representation of knowledge is through a limited repository of qualitative abstractions.
Qualitative Spatio-Temporal Reasoning: Qualitative Spatio-Temporal Reasoning encompasses all techniques of qualitative representation and reasoning about spatial change and spatial interactions.
Qualitative Motion: Description of motion in a more cognitive kind of approach characterized by processing spatial information.