"Geography as War and Peace", Andy Evans, Workshop on Geographic Ontologies Grounding and Vagueness, in Ilkley, UK, 17th April 2008.
You might also like to read:
Evans, A.J. and Waters, T. (2007), 'Mapping Vernacular Geography: Web-based GIS Tools for Capturing "Fuzzy" or "Vague" Entities' International Journal of Technology, Policy and Management, 7, (2) 134-150.
Which includes stuff on capturing vernacular geography, sorites/vagueness, and spatial objects as beliefs. Feel free to email Andy Evans for copies if you don't have access.