, Volume 75, Issue 1, pp 67–84 | Cite as

Ontic Structural Realism and the Principle of the Identity of Indiscernibles

Original Article


Recently, there has been a debate as to whether or not the principle of the identity of indiscernibles (the PII) is compatible with quantum physics. It is also sometimes argued that the answer to this question has implications for the debate over the tenability of ontic structural realism (OSR). The central aim of this paper is to establish what relationship there is (if any) between the PII and OSR. It is argued that one common interpretation of OSR is undermined if the PII turns out to be false, since it is committed to a version of the bundle theory of objects, which implies the PII. However, if OSR is understood as the physical analogue of (sophisticated) mathematical structuralism then OSR does not imply the PII. It is further noted that it is (arguably) a virtue of OSR that it is compatible with a version of the PII for possible worlds.


  1. Ainsworth, P. M. (2010). What is ontic structural realism? Studies in History and Philosophy of Modern Physics, 41(1), 50–57.CrossRefGoogle Scholar
  2. Black, M. (1952). The Identity of indiscernibles. Mind, 61, 153–164.CrossRefGoogle Scholar
  3. Burgess, J. (1999). Review of Stewart Shapiro, philosophy of mathematics: Structure and ontology. Notre Dame Journal of Formal Logic, 40, 283–291.CrossRefGoogle Scholar
  4. Button, T. (2006). Realistic structuralism’s identity crisis: A hybrid solution. Analysis, 66(3), 216–222.CrossRefGoogle Scholar
  5. Dieks, D., & Versteegh, M. A. M. (2008). Identical quantum particles and weak discernibility. Foundations of Physics, 38, 923–934.CrossRefGoogle Scholar
  6. Esfeld, M. (2004). Quantum entanglement and a metaphysics of relations. Studies in History and Philosophy of Modern Physics, 35, 601–617.CrossRefGoogle Scholar
  7. Esfeld, M., & Lam, V. (2008). Moderate structural realism about space-time. Synthese, 160, 27–46.CrossRefGoogle Scholar
  8. Forrest, P. (2006). The identity of indiscernibles. Stanford Encyclopedia of Philosophy, from
  9. French, S. (2006). Identity and individuality in quantum theory. Stanford Encyclopedia of Philosophy, from
  10. French, S. (2010). The interdependence of structure, objects and dependence. Synthese, 175, 89–109.CrossRefGoogle Scholar
  11. Keränen, J. (2001). The identity problem for realist structuralism. Philosophia Mathematica, 3, 308–330.CrossRefGoogle Scholar
  12. Ketland, J. (2006). Structuralism and the identity of indiscernibles. Analysis, 66(4), 303–315.CrossRefGoogle Scholar
  13. Ladyman, J. (1998). What is structural realism? Studies in the History and Philosophy of Science, 29(3), 409–424.CrossRefGoogle Scholar
  14. Ladyman, J. (2007a). Structural realism. Stanford Encyclopaedia of Philosophy, from
  15. Ladyman, J. (2007b). On the identity and diversity of objects in a structure. Proceedings of the Aristotelian Society supplementary Volume LXXXVI, 23–43.Google Scholar
  16. Ladyman, J., & Bigaj, T. (2010). The principle of the idenity of indiscernibles and quantum mechanics. Philsoophy of Science, 77, 117–136.CrossRefGoogle Scholar
  17. Ladyman, J., & Ross, D. (2007). Every thing must go. Oxford: Oxford University Press.CrossRefGoogle Scholar
  18. Leitgib, H., & Ladyman, J. (2008). Criteria of identity and structuralist ontology. Philosophia Mathematica, 16, 388–396.CrossRefGoogle Scholar
  19. MacBride, F. (2006). What constitutes the numerical diversity of mathematical objects. Analysis, 66(1), 63–69.CrossRefGoogle Scholar
  20. Morganti, M. (2004). On the preferability of epistemic structural realism. Synthese, 142, 81–107.CrossRefGoogle Scholar
  21. Muller, F. A. (forthcoming). Withering Away, Weakly. Synthese. doi:10.1007/s11229-009-9609-6
  22. Muller, F. A., & Saunders, S. (2008). Discerning fermions. British Journal for Philosophy of Science, 59, 499–548.CrossRefGoogle Scholar
  23. Muller, F. A., & Seevinck, M. P. (2009). Discerning elementary particles. Philosophy of Science, 76, 179–200.CrossRefGoogle Scholar
  24. Parsons, C. (1990). The structuralist view of mathematical objects. Synthese, 84, 303–346.CrossRefGoogle Scholar
  25. Pooley, O. (2006). Points, particles and structural realism. In D. Rickles, S. French, & J. Saatsi (Eds.), Structural foundations of quantum gravity (pp. 83–120). Oxford: Oxford University Press.Google Scholar
  26. Quine, W. V. O. (1976). Grades of discriminability. Journal of Philosophy, 73, 113–116.CrossRefGoogle Scholar
  27. Rodriguez-Pereyra, G. (2004). The bundle theory is compatible with distinct but indiscernible particulars. Analysis, 64(1), 72–81.CrossRefGoogle Scholar
  28. Saunders, S. (2003a). Physics and Leibniz’s Principles. In K. Brading & E. Castellani (Eds.), Symmetries in physics: Philosophical reflections. Cambridge: Cambridge University Press.Google Scholar
  29. Saunders, S. (2003b). Structural realism again. Synthese, 126, 127–133.CrossRefGoogle Scholar
  30. Saunders, S. (2006). Are quantum particles objects? Analysis, 66(1), 52–63.CrossRefGoogle Scholar
  31. Shapiro, S. (1997). Philosophy of mathematics: Structure and ontology. Oxford: Oxford University Press.Google Scholar
  32. Shapiro, S. (2008). Identity, indiscernibility, and ante rem structuralism: The tale of i and–i. Philosophia Mathematica (III), 16(3), 285–309.CrossRefGoogle Scholar
  33. Stachel, J. (2006). Structure, individuality and quantum gravity. In D. Rickles, S. French, & J. Saatsi (Eds.), Structural foundations of quantum gravity (pp. 53–82). Oxford: Oxford University Press.Google Scholar

Copyright information

© Springer Science+Business Media B.V. 2011

Authors and Affiliations

  1. 1.Department of PhilosophyUniversity of BristolBristolUK

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