The Issue of Perspectivality in Formal Theories of Spatial Representation Author Marion Haemmerli Supervisors Michael Esfeld, University of Lausanne and Achille Varzi, Columbia University Studies/Stag PhD 2nd year e Affiliation University of Lausanne, Switzerland E-Mail marion.haemmerli@unil.ch Aims and Objectives of the Research The aim of my research is to develop a formal theory of spatial representation able to account for perspective-dependent spatial concepts. In my current project I develop a formal ontological theory for reasoning about perspective-dependent locations and I show how perspective-dependent spatial concepts relate to the framework of detached locational concepts. Thus, my aim is to investigate both the philosophical nature of perspective- dependent locational concepts and the way in which they fit into formal ontological theories of spatial representation. While interested in a computationally efficient theory, my main focus is on the conceptual adequacy of the framework I shall propose. Justification for the Research Topic Ever since Hayes’ Naïve Physics Manifesto [4], Qualitative Spatial Reasoning has been a flourishing branch of a common-sense approach to modelling human behaviour in autonomous machines. The question of perspectivality in spatial orientation and of perspective-dependent spatial relations has again and again been in the focus of qualitative calculi of spatial representation (see e.g., [5]). Moreover, perspective-dependent locational concepts are widespread in human discourse and appear in the language practices of a variety of disciplines (ranging from geographic navigation to the bio-medical practice). However, the question of perspective-dependent spatial concepts and their relation to the framework of absolute locational concepts has not been examined so far from a philosophical perspective on formal ontology. As a result, important parts of the relevant literature ignore issues that are related to the question of embedding perspectivality into existent location theories in a conceptually and ontologically adequate manner. In my research, I try to develop a framework for both computationally adequate theories of perspective-dependent spatial representation and philosophically intriguing questions as to the precise nature of perspective-dependent location. I build this framework on mereotopological background structures (often found in bio-medical ontologies) that are able to support entities of different metaphysical kinds. Research Questions 1 Definition of perspectival spatial representations: - What kind of spatial representations count as perspective-dependent representations? - What is the formal structure of perspective-dependent spatial expressions? 2 Formal account of perspectivality - How should perspective-dependency be formally captured? What is a “point of view” and what is its role in a formal account of perspective-dependency? - How should the dependency between a point of view and the corresponding entity be expressed? - What principles rule perspective-dependent spatial expressions? 3 Perspectivality within a theory of spatial representation - What is the conceptually correct account of the relationship between detached, absolute concepts of spatial location and their perspective-dependent counterparts? - What kind of mereo-topological background theory is best suited to support an extension towards location theories that account for perspective-dependent locations? Research Methodology The aim of developing a framework for perspectival spatial concepts translates into two different, though related subtasks. First of all, my concern is to determine a theory of spatial representation that provides an adequate background theory for a formalism able to account for perspectival spatial concepts. In this respect I am focusing on mereotopological theories in the spirit of Achille Varzi’s and Roberto Casati’s theory of spatial representation [1], [2], able to support complex extended formalisms that distinguish between a variety of metaphysical categories (e.g., spatial regions and tenants, material objects and events, abstracta and concrete, etc., see [3]). I shall propose new axiomatic principles for the mereotopological background theory to make it even more suitable as a unified formal- ontological framework for entities of different metaphysical kinds. Second, I shall propose a first-order extension of the adequate meretopological background theory with the aim to include perspective-dependent locational concepts. I am concerned with both an adequate semantics and the relevant corresponding axiomatic principles that rule my first-order formalism for perspective-dependent locations. Research Results to Date - Clarification of the nature and definition of perspectival locational concepts. - Development of a first-order formalism for expressing perspective-dependent spatial concepts on the basis of Achille Varzi’s Kuratowski Extension of General Extensional Mereology (KGEMT) and his theory of location [2]. - Development of a semantic model for my theory. - New mereo-topological axioms for KGEMT - Some first axiomatic principles for my formalism. References 1. Varzi A, Casati R (1999), Parts and Places, Cambridge, Mass., The MIT Press. 2. Varzi A (2007), Parts, Wholes, and Locations, in: I Pratt-Hartmann (ed.), Handbook on Spatial Logic, Berlin : Springer Verlag. 3. Gangemi A, Guarino N, Masolo C, Oltramari A (2003) Sweetening Ontologies with DOLCE, in: Proceedings of EKAW02, Siguenza, Spain, Springer, 166-181. 4. Hayes P (1979), The Naïve Physics Manifesto, in: D Michie (ed.), Expert Systems, Edinburgh: Edinburgh University Press. 5. Cohn A, Renz J (2008), Qualitative Spatial Representation and Reasoning, in: Harmelen F, Lifschitz V, Porter B (eds.), Handbook of Knowledge Representation, Amsterdam, The Netherlands and Oxford, UK, Elsevier.