Parts, wholes, and part-whole relations: The prospects of mereotopology

Abstract

We can see mereology as a theory of parthood and topology as a theory of wholeness. How can the two be combined to obtain a unified theory of parts and wholes'? This paper examines three main ways of answering this question. On the first account, mereology and topology form two independent (though mutually related) domains. The second account grants priority to topology and characterizes mereology derivatively, by defining parthood in terms of wholeness (more specifically: connectedness). The third approach reverses the order, exploiting the idea that wholeness (connectedness) can be explained in terms of parthood along with other predicates or relations. The analysis and comparison of these strategies is mostly formal (and within the confines of standard first-order theories), but their relevance to spatio-temporal reasoning and representation is emphasized. Some more speculative strategies and directions for further research, such as the development of a unified framework based on a single mereotopological primitive of connected parthood, are also briefly considered.