Title: Classical Mereology and Plural Identity
Speaker: Byeong-uk Yi (University of Toronto)
Time: 2024/03/26 15:10-18:00
Location: Room 313, Teaching Building No.2 (第二教学楼), Peking University
Abstract:
Say that some things compose one thing, if the latter is, roughly, a whole, fusion, or mereological sum of the former things. Then the thesis of composition as identity (CAI) states that some things compose something if and only if the former things (taken together) are the same things as the latter thing. We can find a version of the thesis in Plato's Theaetetus [6, 201e–206b], and David Lewis's suggestion of the thesis instigated modern debates about the thesis. This article show that the thesis is incoherent by proving that it is logically equivalent to the (part-whole) triviality thesis, the thesis that everything is a part of itself but of nothing else. In doing so, it distinguishes three formulations of the thesis resulting from different analyses of the composition relation and proves that all the three formulations are logically equivalent to the triviality thesis. The proof involves the basics of plural logic presented in, e.g., [1, 2] and improves on the proof given in [3, 4].
1. Yi, B.-U. 2005. The Logic and Meaning of Plurals. Part I. Journal of Philosophical Logic 34: 459–506.
2. Yi, B.-U. 2006. The Logic and Meaning of Plurals. Part II. Journal of Philosophical Logic 35: 239–288.
3. Yi, B.-U. 2014. Is there a plural object? In A. J. Cotnoir and D. Baxter, Composition as Identity (Oxford: Oxford University Press, 2014): 169–191.
4. Yi, B.-U. 2021. Is composition identity? Synthese 198(Suppl 18): S4467–S4501.
Bio:
Professor Byeong-uk Yi is a philosopher at the University of Toronto who specializes in metaphysics and philosophy of language, logic and philosophy of mathematics. His recent work focuses on the nature of the many as such, and the logic and meaning of expressions used to talk about them, such as plural constructions found in English and many other natural languages. He also works on the nature of stuff, semantics of mass nouns, semantics of classifiers of East Asian languages (e.g., Korean, Chinese, Japanese), and some issues in philosophy of science, decision theory, and history of philosophy. He has published a book, Understanding the Many (Routledge, 2002), and many articles in international academic journals in philosophy and logic, and is working on a book on plural constructions, Plurals: Their Logic and Semantics.