Skip to main content

Absolute Infinity in Class Theory and in Theology

  • Chapter
  • First Online:
Objectivity, Realism, and Proof

Part of the book series: Boston Studies in the Philosophy and History of Science ((BSPS,volume 318))

  • 556 Accesses

Abstract

In this article we investigate similarities between the role that ineffability of Absolute Infinity plays in class theory and in theology.

How can I talk to you, I have no words

Virgin Prunes, I am God

Versions of this article have been presented at various conferences and workshops, including at the First Conference of the Italian Network for the Philosophy of Mathematics (Milan 2014). I am grateful to the audiences at these events for invaluable questions, comments and suggestions. Among these, I am especially indebted to Anthony Anderson, Sam Roberts, Øystein Linnebo, Mark van Atten, Christian Tapp. Thanks also to two anonymous referees, for giving careful suggestions for improvement. But above all I am grateful to my colleague Philip Welch: I could never have written this article without the discussions that I have had with him about proper classes and reflection.

This is a preview of subscription content, log in via an institution to check access.

Access this chapter

Chapter
USD 29.95
Price excludes VAT (USA)
  • Available as PDF
  • Read on any device
  • Instant download
  • Own it forever
eBook
USD 109.00
Price excludes VAT (USA)
  • Available as EPUB and PDF
  • Read on any device
  • Instant download
  • Own it forever
Softcover Book
USD 139.99
Price excludes VAT (USA)
  • Compact, lightweight edition
  • Dispatched in 3 to 5 business days
  • Free shipping worldwide - see info
Hardcover Book
USD 139.99
Price excludes VAT (USA)
  • Durable hardcover edition
  • Dispatched in 3 to 5 business days
  • Free shipping worldwide - see info

Tax calculation will be finalised at checkout

Purchases are for personal use only

Institutional subscriptions

Notes

  1. 1.

    For one expression of this view, see Jané (1995).

  2. 2.

    Zermelo here means a series of initial segments \(V_{\alpha }\) of the set theoretic universe V, for \(\alpha \) ranging over the strongly inaccessible ordinals, and the membership relation restricted \(V_{\alpha }\).

  3. 3.

    In this quotation, Cantor speaks of the necessity of ‘knowing’ the domain of variation through a ‘definition’. Surely Cantor is merely sloppy here, and we should discount the epistemological overtones. Another slip can be detected in Cantor’s use of the word ‘set’ in this quotation: Cantor means the argument to be applicable not just to sets but also to absolute infinities. For a discussion of Cantor’s sometimes sloppy uses of the term ‘set’, see Jané (2010), footnote 60.

  4. 4.

    The connection between Cantor’s conception of the mathematical absolutely infinite and his conception of God is explored in van der Veen and Horsten (2014).

  5. 5.

    For Cantor’s most detailed account of the set theoretic universe in God’s mind, see Tapp (2005), pp. 414–417. See also Mitteilungen zur Lehre vom Transfiniten V, footnote 3 (Cantor 1932, pp. 401–403).

  6. 6.

    This notion goes back to Anaximander, and is variously translated as ‘limitless’,’boundless’, ‘formless’, ‘the void’....

  7. 7.

    Cantor’s 1899 argument that the ordinals form an inconsistent totality is critically discussed in Jané (1995), pp. 395–396.

  8. 8.

    Admittedly this passage is sufficiently vague as to be open to multiple interpretations. The view that this passage should be seen as an application of reflection is defended in Hallett (1984), pp. 117–118.

  9. 9.

    The Montague-Levy reflection principle is discussed in Drake (1991), Chap. 3, Sect. 6.

  10. 10.

    Ranks \(V_{\alpha }\), for \(\alpha \) strongly inaccessible, are models of \(ZFC^2\).

  11. 11.

    NBG differs from full \(ZFC^2\) in that the second-order comprehension scheme is restricted to formulae that do not contain bound occurrences of second-order quantifiers.

  12. 12.

    See von Neumann (1967).

  13. 13.

    Axiom 2 and its relatives were discussed in Bernays (1961). For a discussion of indescribable cardinals, see Drake (1991), Chap. 9.

  14. 14.

    Parameter free sentences of higher orders are unproblematic.

  15. 15.

    We will see later (Sect. 7.6.3) that the expression “any assertions” in this statement may need to be qualified.

  16. 16.

    A philosophical defence of GRP is given in Horsten and Welch (forthcoming).

  17. 17.

    The large cardinal strength of versions of GRP is discussed in Horsten and Welch (forthcoming) and in Welch (2012).

  18. 18.

    “Quomodo potest finitum attingere ad infinitum? Propter hoc dixerunt alii quod deus contemperatum se exhibebit nobis, et quod ostendet se nobis non in sua essentia, sed in creatura”.

  19. 19.

    As quoted in Segal (1977), p. 163.

  20. 20.

    I am indebted to an anonymous referee for these points.

  21. 21.

    See also Horsten and Welch (forthcoming).

  22. 22.

    Even the Augustinian idea that sets are ideas in God’s mind is compatible with this view. Within such a framework, the mereological conception of classes would result in conceiving of classes (proper and improper) as parts of God’s mind.

  23. 23.

    It seems to me that Maddy’s own view of classes does not completely satisfy the first desideratum. The reason is that she takes the class membership relation to be governed by partial logic. According to her theory, there is in many cases no fact of the matter whether a given class is an element of another given class.

  24. 24.

    See the quotation of Dionysius in Sect. 7.5.

  25. 25.

    This argument does not go through if instead j is only \(\Sigma ^0_{1}\) elementary: there is then not enough elementarity to preserve the impredicative second order comprehension scheme upwards. Nonetheless, since MK holds at \((V_{\kappa }, V_{\kappa +1}, \in \)), accepting \(GRP_{\Sigma ^0_{1}}\) still commits one to believing that impredicative second-order logic is at least coherent.

  26. 26.

    See Gödel (1984).

References

  • Bernays, P. (1961). Zur Frage der Unendlichkeitsschemata in der axiomatische Mengenlehre. In Essays on the foundations of mathematics, (pp. 3–49). Oceanside: Magnus Press.

    Google Scholar 

  • Boolos, G. (1985). Nominalist platonism. Philosophical Review, 94, 327–344.

    Article  Google Scholar 

  • Burali-Forti, C. (1897). Una questione sui numeri transfiniti. Rendiconti del Circolo Matematico di Palermo, 11, 154–164.

    Article  Google Scholar 

  • Cantor, G. (1932). Abhandlungen mathematischen und philosophischen Inhalts. Herausgegeben von Ernst Zermelo: Verlag Julius Springer.

    Google Scholar 

  • Cantor, G. (1991). Briefe, Herausgegeben von Herbert Meschkowski und Winfried Nilson. Berlin: Springer.

    Google Scholar 

  • Côté, A. (2002). L’infinité divine dans la théologie médiévale (1220–1255). Berlin: Vrin.

    Google Scholar 

  • Dionysius the Areopagite (1920). In C. E. Rolt (Ed.), On the divine names and the mystical theology. Christian Classics Ethereal Library.

    Google Scholar 

  • Drake, F. (1991). Set theory. An introduction to large cardinals. North-Holland.

    Google Scholar 

  • Feferman, S. (1991). Reflecting on Incompleteness. Journal of Symbolic Logic, 56, 1–49.

    Article  Google Scholar 

  • Gödel, K. (1990). What is Cantor’s continuum problem? In: Gödel, K., Collected Works, Volume II: Publications 1938–1974 (pp. 254–270). Oxford: Oxford University Press.

    Google Scholar 

  • Gödel, K. (1984). Russell’s mathematical logic. Reprinted in: P. Benacerraf & H. Putnam (Eds.), Philosophy of mathematics: Selected readings (2nd ed., pp. 447–469). Cambridge: Cambridge University Press.

    Google Scholar 

  • Hallett, M. (1984). Cantorian set theory and limitation of size. Oxford: Clarendon Press.

    Google Scholar 

  • Hauser, K. (2013). Cantor’s Absolute in metaphysics and mathematics. International Philosophical Quarterly, 53, 161–188.

    Article  Google Scholar 

  • Horsten, L., & Welch, P. (forthcoming). Absolute Infinity. Journal of Philosophy.

    Google Scholar 

  • Jané, I. (1995). The role of the absolutely infinite in Cantor’s conception of set. Erkenntnis, 42, 375–402.

    Article  Google Scholar 

  • Jané, I. (2010). Idealist and realist elements in Cantor’s approach to set theory. Philosophia Mathematica, 18, 193–226.

    Article  Google Scholar 

  • Kanamori, A. (1994). The higher infinite Large cardinals in set theory from their beginnings. Berlin: Springer.

    Google Scholar 

  • Koellner, P. (2009). On reflection principles. Annals of Pure and Applied Logic, 157, 206–219.

    Article  Google Scholar 

  • Lewis, D. (1991). Parts of classes. Oxford: Basil Blackwell.

    Google Scholar 

  • Lewis, D. (1993). Mathematics is megethology. Philosophia Mathematica, 3, 3–23.

    Article  Google Scholar 

  • Maddy, P. (1983). Proper classes. The Journal of Symbolic Logic, 48, 113–139.

    Article  Google Scholar 

  • Reinhardt, W. (1974). Remarks on reflection principles, large cardinals, and elementary embeddings. In: Proceedings of Symposia in Pure Mathematics (Vol. 10, pp. 189–205). Providence: American Mathematical Society.

    Google Scholar 

  • Segal, A. (1977). Two powers in heaven. Early rabbinic reports about christianity and gnosticism. Brill.

    Google Scholar 

  • Tait, W. (2001). Gödel’s unpublished papers on the foundations of mathematics. Philosophia Mathematica, 9, 87–126.

    Article  Google Scholar 

  • Tait, W. (Ed.). (2005). Constructing cardinals from below. In The provenance of pure reason: Essays in the philosophy of mathematics and its history (pp. 133–154). Oxford: Oxford University Press.

    Google Scholar 

  • Tapp, C. (2005). Kardinalität und Kardinäle: Wissenschaftshistorische Aufarbeitung der Korrespondenz zwischen Georg Cantor und katholischen Theologen seiner Zeit. Franz Steiner.

    Google Scholar 

  • Tapp, C. (2014). Absolute Infinity—a bridge between mathematics and theology? In H. Friedman & N. Tennant (Eds.), Foundational adventures. Essays in honor of Harvey M. Friedman (pp. 77–90). College Publications.

    Google Scholar 

  • Uzquiano, G. (2003). Plural quantification and classes. Philosophia Mathematica, 11, 67–81.

    Article  Google Scholar 

  • van Atten, M. (2009). Monads and sets. On Gödel, Leibniz, and the reflection principle. In G. Primiero & S. Rahman (eds.), Judgement and Knowledge. Papers in honour of B.G. Sundholm. College Publications, pp. 3–33.

    Google Scholar 

  • van der Veen, J., & Horsten, L. (2014). Cantorian infinity and philosophical concepts of god. European Journal for the Philosophy of Religion, 5, 117–138.

    Google Scholar 

  • von Neumann, J. (1967). An axiomatization of set theory. In J. Van Heijenoort (Ed.), From Frege to Gödel. A source book in mathematical logic (1879–1931). Massachusetts: Harvard University Press.

    Google Scholar 

  • Wang, H. (1996). A logical journey. From gödel to philosophy. Massachusetts: MIT Press.

    Google Scholar 

  • Welch, P. (2012, June). Global reflection principles. Paper prepared for Exploring the frontiers of incompleteness. Isaac Newton Institute Pre-print Series, No. INI12050-SAS.

    Google Scholar 

  • Zermelo, E. (1996). On boundary numbers and domains of sets. (M. Hallett, Trans.). In: W. Ewald (Ed.), From Kant to Hilbert: A source book in mathematics (Vol. 2, pp. 1208–1233). Oxford: Oxford University Press.

    Google Scholar 

Download references

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Leon Horsten .

Editor information

Editors and Affiliations

Rights and permissions

Reprints and permissions

Copyright information

© 2016 Springer International Publishing Switzerland

About this chapter

Cite this chapter

Horsten, L. (2016). Absolute Infinity in Class Theory and in Theology. In: Boccuni, F., Sereni, A. (eds) Objectivity, Realism, and Proof . Boston Studies in the Philosophy and History of Science, vol 318. Springer, Cham. https://doi.org/10.1007/978-3-319-31644-4_7

Download citation

Publish with us

Policies and ethics