A study in early medieval mereology: Boethius, Abelard, and pseudo-Joscelin
Arlig, Andrew W.
Doctor of Philosophy, Ohio State University, Philosophy, (2005)
The study of parts and wholes, or mereology, occupies two of the best philosophical minds of twelfth-century Europe, Abelard and Pseudo-Joscelin. But the contributions of Abelard and Pseudo-Joscelin cannot be adequately assessed until we come to terms with the mereological doctrines of the sixth century philosopher Boethius. Apart from providing the general mereological background for the period, Boethius influences Abelard and Pseudo-Joscelin in two crucial respects. First, Boethius all but omits mention of the classical Aristotelian concept of form. Second, Boethius repeatedly highlights a rule which says that if a part is removed, the whole is removed as well. Abelard makes many improvements upon Boethius. His theory of static identity accounts for the relations of sameness and difference that hold between a thing and its part. His theory of identity also provides a solution to the problem of material constitution. With respect to the problem of persistence, Abelard assimilates Boethius’ rule and proposes that the loss of any part entails the annihilation of the whole. More precisely, Abelard thinks that the matter of things suffers annihilation upon the gain or loss of even one part. He also holds that many structured wholes, namely artifacts, are strictly dependent upon their parts. Yet Abelard insists that human beings survive a variety of mereological changes. Abelard is silent about objects which are neither artifacts nor persons. I argue that Abelard has the theoretical resources to provide an account of the persistence of these types of object, so long as some forms are ontologically robust. Pseudo-Joscelin rejects the thesis that the removal of any part entails the destruction of the whole. The annihilation of a whole follows only from the removal of essential parts. Pseudo-Joscelin employs two basic principles in his theory of persistence. First, forms and the functions encoded in them play a primary role in identity and persistence. He also makes use of a genetic criterion. Pseudo-Joscelin expands both principles and employs them when he vigorously defends the thesis that a universal is a concrete whole composed of particulars from Abelard’s criticisms.