Abstract
In this paper, we argue for an instrumental form of existence, inspired by Hilbert’s method of ideal elements. As a case study, we consider the existence of contradictory objects in models of non-classical set theories. Based on this discussion, we argue for a very liberal notion of existence in mathematics.
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Acknowledgments
We thank the many useful suggestions and corrections of two anonymous referees, who helped to improve and to correct many aspects of our work. We also thank the Journal of Philosophical Logic for the careful and professional editorial work. The first author acknowledges support from the FAPESP grant. n. 2017/23853-0. The second author wants to acknowledge FAPESP for providing him a Visiting Researcher grant (n. 2016/25891-3) to spend one year at the Philosophy Department of the University of Campinas. The third author acknowledges support from FAPESP, Jovem Pesquisador grant (n. 2016/25891- 3), and from CNPq grant (n. 301108/2019-6).
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Jockwich, S., Tarafder, S. & Venturi, G. Ideal Objects for Set Theory. J Philos Logic 51, 583–602 (2022). https://doi.org/10.1007/s10992-021-09642-4
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DOI: https://doi.org/10.1007/s10992-021-09642-4