A Causal Perspective to Qualitative Spatial Reasoning in the Situation Calculus Mehul Bhatt 1 , Wenny Rahayu 1 , and Gerald Sterling 2 1 Department of Computer Science La Trobe University Melbourne, Australia 3086 Tel.: +61-3-94791280 {mbhatt, wenny}@cs.latrobe.edu.au 2 Air-Operations Division Defence Science Technology Organisation P.O. Box 4331 Melbourne Australia 3001 Tel.: +61-3-96267728 Gerald.Sterling@dsto.defence.gov.au Abstract. We propose the utilisation of a general formalism to reason about ac- tion & change for reasoning about the dynamic purpose-directed aspects of spa- tial change. Such an approach is necessary toward the general integration of qual- itative spatial reasoning with reasoning about the teleological aspects of spatial change. With this as the overall context, the main contribution of this paper is to illustrate first ideas relevant to providing a causal perspective to qualitative spa- tial reasoning using the situation calculus. With minimal notions about space & spatial dynamics, we perform a naive characterisation of objects based on their physical properties and investigate the key representational aspects of a topo- logical theory of space, namely the region connection calculus, in the situation calculus. Further, ontological distinctions are made between various occurrents, i.e., actions and internal & external events, and a domain level characterisation of spatial occurrents in terms of their spatial pre-conditions & effects is performed so as to provide a causal perspective to spatial reasoning. 1 Introduction Qualitative spatial reasoning (QSR) is an abstraction from precision oriented quantita- tive reasoning about the physical world [1]. Most research in qualitative spatial reason- ing has focused on particular aspects of space such as topology [12], orientation [5], distance [7] etc and their integration thereof. However, relatively little work has ex- plicitly addressed the need to account for the dynamic teleological or purpose-directed aspects of spatial change within a unified setup. Whereas qualitative spatial reasoning is concerned with the manner in which a set of spatial relationships evolve during a certain time interval, reasoning about the teleological aspects of a system involves reasoning about action and encompasses the goal directed aspects of spatial change. E.g., con- sider a travelling task from location L 1 to L 2 – Minimally, there are two main closely related aspects to this problem: (a) Spatial: The specific sequence of spatial transfor- mations needed in order to achieve a certain desired configuration as well as its legality J.S. Sichman et al. (Eds.): IBERAMIA-SBIA 2006, LNAI 4140, pp. 430–440, 2006. c  Springer-Verlag Berlin Heidelberg 2006