Hostname: page-component-cd9895bd7-8ctnn Total loading time: 0 Render date: 2024-12-23T03:17:35.605Z Has data issue: false hasContentIssue false

Stanisław Leśniewski: Rethinking the Philosophy of Mathematics

Published online by Cambridge University Press:  29 January 2015

Rafal Urbaniak*
Affiliation:
Centre for Logic and Philosophy of Science, Ghent University, Belgium, and Department of Philosophy, Sociology and Journalism, Gdansk University, Poland. E-mail: [email protected]

Abstract

Near the end of the nineteenth century, a part of mathematical research was focused on unification: the goal was to find ‘one sort of thing’ that mathematics is (or could be taken to be) about. Quite quickly sets became the main candidate for this position. While the enterprise hit a rough patch with Frege’s failure and set-theoretic paradoxes, by the 1920s mathematicians (roughly speaking) settled on a promising axiomatization of set theory and considered it foundational. In parallel to this development was the work of Stanislaw Leśniewski (1886–1939), a Polish logician who did not accept the existence of abstract (aspatial, atemporal and acausal) objects such as sets. Leśniewski attempted to find a nominalistically acceptable replacement for set theory in the foundations of mathematics. His candidate was Mereology – a theory which, instead of sets and elements, spoke of wholes and parts. The goal of this paper will be to present Mereology in this context, to evaluate the feasibility of Leśniewski’s project and to briefly comment on its contemporary relevance.

Type
Focus: Logic and Philosophy in Poland
Copyright
© Academia Europaea 2015 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Notes and References

1.‘In the late nineteenth century, it was a widespread idea that pure mathematics is nothing but an elaborate form of arithmetic. Thus it was usual to talk about the arithmetisation of mathematics, and how it had brought about the highest standards of rigor.’ See Ferreirós, J. (2012) The early development of set theory. In: E. N. Zalta (ed.), The Stanford Encyclopedia of Philosophy (http://plato.stanford.edu/cite.html), Winter 2012 edition, section 3.Google Scholar
2.That is, a sequence x 1,x 2,… such that for every rational number ϵ>0 there is an integer n such that for all integers numbers j, i, |x ix j|<ϵ.0+there+is+an+integer+n+such+that+for+all+integers+numbers+j,+i,+|xi−xj|<ϵ.>Google Scholar
3.See Appendix A to remind yourself what these axioms are.Google Scholar
4.See Appendix B for details.Google Scholar
5.For a good anthology of Frege’s basic writings see Beaney, M. (1997) The Frege Reader (Malden, Oxford, Carlton: Wiley-Blackwell).Google Scholar
6.Very roughly speaking, this is a logic that handles reasoning employing not only quantification over objects (‘for all objects x’) but also over properties of objects (e.g. ‘for no x there is a P such that Px and not-Px.’).Google Scholar
7.Frege thought that sets, which he called ‘extensions’, were logical objects, whatever that might mean, so his aim was even more ambitious: to show that mathematics is ultimately just logic.Google Scholar
8.Frege made a distinction between objectively understood concepts, being higher-order items and not lying in the range of first-order quantifiers, and their extensions, which could be treated like objects.Google Scholar
9.Equinumerosity can be defined without reference to numbers: F and G are equinumerous iff there is a 1–1 mapping between objects which are Fs and objects which are Gs.Google Scholar
10.The history of mathematics had to wait till Gödel’s work in 1933 for the birth of the so-called iterative conception of set, according to which sets are built up in stages. This approach is a bit more principled and provides justification for all axioms of standard set theory. (Which doesn’t mean it’s philosophical status isn’t debated nowadays.).Google Scholar
11.This is a fairly natural way to go: Leśniewski first used mereological intuitions to handle Russell’s paradox in 1914, and developed a semi-formalized axiomatization of Mereology in 1916.Google Scholar
12.Nowadays, we rather call ingredients ‘parts’ and what Leśniewski called parts we call ‘proper parts’.Google Scholar
13.S. Leśniewski (1927) O Podstawach Matematyki, Wsętp. Rozdział I: O pewnych kwestjach, dotyczących sensu tez ‘logistycznych’. Rozdział II: O ‘antynomji’ p. Russella, dotyczącej ‘klasy klas, nie będących wł asnemi elementami’. Rozdział III: O różnych sposobach rozumienia wyrazów ‘klasa’ i ‘zbiór’. Przegląd Filozoficzny, 30, pp. 164–206. [On the foundations of mathematics. Introduction. Ch. I. On some questions regarding the sense of the ‘logistic’ theses. Ch. II. On Russel’s ‘antinomy’ concerning ‘the class of classes which are not elements of themselves’. Ch. III. On various ways of understanding the expression ‘class’ and ‘collection’ see Leśniewsk, S. (1991) Stanisław Leśniewski. Collected Works (two vols.), Edited and translated by S. Surma, J. Srzednicki and D. I. Barnett. (Dordrecht: Kluwer Academic), pp. 174226.Google Scholar
14.S. Leśniewski (1916) Podstawy ogólnej teoryi mnogości I. Prace Polskiego Koła Naukowego w Moskwie, 2. (Foundations of the general theory of sets I). see Leśniewsk, S. (1991) Stanisław Leśniewski. Collected Works (two vols.), Edited and translated by S. Surma, J. Srzednicki and D. I. Barnett. (Dordrecht: Kluwer Academic), pp. 129173.Google Scholar
15.Named so after a logician who informed my PhD supervisor that I named my cat after him.Google Scholar
16.Kearns, J. (1962) Lesniewski, Language, and Logic. PhD thesis, Yale University, p. 35.Google Scholar
17.Simons, P. (1993) Nominalism in Poland. In: F. Coniglione, R. Poli and J. Woleński (eds.), Polish Scientific Philosophy: The Lvov-Warsaw School (Amsterdam: Rodopi), p. 7.Google Scholar
18.Hellman, G. (2014) Mereology in philosophy of mathematics. In: Handbook of Mereology (Munich: Philosophia Verlag).Google Scholar
19.Link, G. (1998) Algebraic Semantics in Language and Philosophy (Stanford, USA: CSLI Publications).Google Scholar
20.Champollion, L. (2012) Linguistic applications of mereology. Manuscript.Google Scholar
21.Indriunas, M., Taylor, J. and Raskin, V. (2012) Mereological considerations for improving semantic ontology. Manuscript.Google Scholar
22.Bunt, H. C. (1985) Mass Terms and Model-theoretic Semantics, vol. 295. Cambridge: Cambridge University Press).Google Scholar
23.Klinov, P. and Mazlack, L. J. (2007) On possible applications of rough mereology to handling granularity in ontological knowledge. In: Proceedings of the National Conference on Artificial Intelligence, vol. 22. (Menlo Park, CA; Cambridge, MA; London: AAAI Press; MIT Press), p. 1876.Google Scholar
24.Polkowski, L. and Skowron, A. (2000) Rough mereology in information systems. a case study: qualitative spatial reasoning. In: Rough Set Methods and Applications (Dordrecht: Springer), pp. 89135.Google Scholar