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Naïve Mereology

David H. Sanford

Pages 369 - 371

Two individuals overlap if they have some common content, if something is a portion of each. In standard systems of formal mereology, the following principle is either a definition or a theorem: x is a part of y if and only if everything that overlaps x overlaps y. The entry Sum in this Handbook uses this notion of part after pointing out an appropriate restriction of the domain of discourse to items that overlap something. This entry uses the phrase ‘O-part’ (‘part defined in terms of overlap’) to refer to things that satisfy the above definition. The notion of O-part within formal mereology diverges from many uses of ‘part’ outside formal mereology. ‘Naïve mereology’, an early name for a study of this divergence is not ideal because it suggests a higher degree of theoretical organisation and a firmer identification of basic principles than currently obtains and also because the word ‘naïve’ suggest too narrow a domain. Many uses of ‘part’ in ordinary, or ‘naïve’, speech and thought diverge from the notion of O-part, but so do many uses of ‘part’ in developed sciences such as geology, botany, anatomy, physiology, and engineering (Simons, 2006: 613).

1Department of Philosophy, Duke University

1 Casati, R.; Varzi, A. C., (1994), Holes and Other Superficialities, Cambridge, MIT Press.

2 Casati, R.; Varzi, A. C., (1999), Parts and Places: The Structure of Spatial Representation, Cambridge, MIT Press.

3 Donnelly, M., (2003), “Of Parts and Holes: The Spatial Structure of the Human Body”, IFOMIS Report ISSN 1611-4019, University of Leipzig.

4 Simons, P. M.; Dement, C. W., (1996), “Aspects of the Mereology of Artifacts”, Poli, R.; Simons, P. (eds.), Formal Ontology, Dordrecht, Kluwer. Sanford, D. H., 1996, “Temporal Parts, Temporal Portions, and Temporal Slices: an Exercise in Naïve Mereology”, Acta analytica 15: 21-33.

5 Simons, P., (2006), “Real Wholes, Real Parts: Mereology without Algebra”, Journal of Philosophy 103: 597-630.

6 Varzi, A. C., (2006), “A Note on the Transitivity of Parthood”, Applied Ontology 1: 141-146.

7 Winston, M. E.; Chaffin, R.; Herrman, D., (1987), “A Taxonomy of Part-Whole Relations”, Cognitive Science 11: 417-444.


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