Skip to main content
Log in

Did Tom Kuhn actually Meet Tom Bayes?

Erkenntnis Aims and scope Submit manuscript

Abstract

Wesley Salmon and John Earman have presented influential Bayesian reconstructions of Thomas Kuhn’s account of theory-change. In this paper I argue that all attempts to give a Bayesian reading of Kuhn’s philosophy of science are fundamentally misguided due to the fact that Bayesian confirmation theory is in fact inconsistent with Kuhn’s account. The reasons for this inconsistency are traced to the role the concept of incommensurability plays with reference to the ‘observational vocabulary’ within Kuhn’s picture of scientific theories. The upshot of the discussion is that it is impossible to integrate both Kuhn’s claims and Bayesianism within a coherent account of theory-change.

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

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Notes

  1. What Earman seems to have in mind here is that only theories consistent with the most general propositions delimiting each paradigm can reasonably be thought of within its context. For example, a physical theory in which mass varies with kinetic properties such as velocity could not be taken to lie within the space of possibilities the Newtonian paradigm allows.

  2. I am indebted to an anonymous referee for bringing this point to my attention.

  3. Similar considerations to the conclusion that Bayesianism need not be revised on Earman’s account one can find in Worrall (2000, 137–138). Worrall also explores the following possibility: “So far as I [Worrall] can tell, Earman’s main counter-argument [to the claim that on his own account there is no need to revise Bayesianism] is, indeed, that it [i.e. Bayesianism unrevised] is psychologically unrealistic – the scientists involved in revolutions did not as a matter of fact themselves explicitly internalise the conceptual possibilities that make it possible to see the dispute as occurring against an agreed conceptual background” (138). On this reading, nonetheless, it is surely very unclear how descriptive psychological considerations, which are located within the context of discovery, can have any impact whatsoever on Bayesianism, which is a normative theory located within the context of justification.

  4. A considerable amount of the recent literature on Kuhnian philosophy of science has been devoted to showing that Kuhn’s own inference from incommensurability to epistemological anti-realism is unwarranted (Sankey 1997, 1998; Bird 2000, 2003). This new reading though is highly controversial and rather orthogonal to my main purposes in this paper, which are not to inquire about the status of Kuhn’s anti-realism but rather investigate whether his account of the meaning of the so-called ‘observational terms’ tunes well with the one that Bayesian confirmation theory assumes.

  5. For instance see Boyd (1984, pp. 59–60), where the important point is raised that on a strict understanding of holism, there can be no “crises” the way Kuhn wants it, since all the evidence within the paradigm is by definition supportive of it.

  6. This objection seems to assume a personalist Bayesian framework of analysis according to which the only constraints in the assignment of priors are the formal axioms of probability. It seems, though, that even on a frequentist approach like Salmon’s one could restate the objection on the grounds that what constitutes “our best estimates of the frequencies with which certain kinds of hypotheses succeed” (Salmon 1990, p. 187) is equally context dependent, since the notion of ‘empirical success’ itself can plausibly be held to be context sensitive on a Kuhnian reading.

  7. A similar Kantian reading of Kuhn’s philosophy in all its details has also been put forth by Hoyningen-Huene (1993).

  8. Returning to the new strand within Kuhnian scholarship referred to in footnote 4, I do not believe that proponents of this view need to disagree with my argument, as the following assertion of Bird’s indicates: “[T]here is no particular reason to think that, in general, revolutions bring with them changes in the meanings of perceptual vocabulary, although it is quite possible that a revolution concerning paradigms with a highly perceptual element could lead to incommensurability of this sort” (2000, p. 204).

  9. The expression “for her” is not intended to imply a qualification of my claims, in the sense that there might be a neutral basis suitable for the reconciliation of Kuhn and Bayes and which is merely accidentally unknown to our agent. Actually, the whole point, according to Kuhn, is that there cannot be such a basis. Observation has to be community relative and since our agent has to be a member of one, the same holds for theory choice as well.

  10. Of course this generalises easily to the case where many competitors are involved.

  11. I owe the exploration of this possibility to an anonymous referee.

  12. Worrall (2000, 133) seems to overlook this objective element of Bayesianism when he complains about the subjectivity of the prior probability of the evidence P(E).

References

  • Bird, A. (2000). Thomas Kuhn. London: Acumen

    Google Scholar 

  • Bird, A. (2003). Kuhn, nominalism and empiricism. Philosophy of Science, 70, 690–719

    Article  Google Scholar 

  • Boyd, R. (1984). The current status scientific realism. In J. Leplin (Ed.), Scientific Realism. Berkeley: University of California Press

    Google Scholar 

  • Earman, J. (1992). Bayes or Bust? A critical examination of Bayesian confirmation theory. Cambridge: MA, MIT Press

    Google Scholar 

  • Friedman, M. (1999a). Geometry, convention and the relativised a priori: Reichenbach, Schlick and Carnap. In Reconsidering Logical Positivism, Cambridge: Cambridge University Press

  • Friedman, M. (1999b). Poincare’s conventionalism and the logical positivists. In Reconsidering Logical Positivism, Cambridge: Cambridge University Press

  • Friedman, M. (2001). Dynamics of Reason. Stanford, California: CSLI Publications

    Google Scholar 

  • Hoyningen-Huene, P. (1993). Reconstructing scientific revolutions. Chicago and London: The University of Chicago Press

    Google Scholar 

  • Kuhn, T. S. (1962–1970). The structure of scientific revolutions. Chicago and London: The University of Chicago Press

  • Kuhn, T. S. (1973). Objectivity, value judgement, and theory choice, In The Essential Tension. Chicago and London: The University of Chicago Press, 1977

  • Kuhn, T. S. (1982). Commensurability, comparability, communicability, PSA: Proceedings of the Biennial Meeting of the Philosophy of Science Association. Vol. 2, Symposia and Invited Papers, pp. 669–88

  • Kuhn, T. S. (1983). Rationality and theory choice. The Journal of Philosophy, 80, 563–70

    Article  Google Scholar 

  • Kuhn, T. S. (1993). Afterwords. In P. Horwich (Ed.), World changes: Thomas Kuhn and the nature of science. Cambridge Mass: MIT Press

    Google Scholar 

  • Reichenbach, H. (1920). The theory of relativity and a priori knowledge. Los Angeles: University of California Press

    Google Scholar 

  • Salmon, W. C. (1990). Rationality and objectivity in science or Tom Kuhn meets Tom Bayes. In C. W. Savage (Ed.), Scientific Theories, Minnesota Studies in the Philosophy of Science, Vol. 14. Minneapolis: University of Minnesota Press

    Google Scholar 

  • Sankey, H. (1997). Incommensurability: The current state of play. Theoria, 12, 425–45

    Google Scholar 

  • Sankey, H. (1998). Taxonomic incommensurability. International Studies in the Philosophy of Science, 12, 7–16

    Article  Google Scholar 

  • Worrall, J. (2000). Kuhn, Bayes and ‘Theory-Choice: How revolutionary is Kuhn’s account of theoretical change? In R. Nola, & H. Sankey (Eds.), After Popper, Kuhn and Feyerabend. Amsterdam: Kluwer Academic Publishers

    Google Scholar 

Download references

Acknowledgements

I am especially grateful to Stephan Hartmann and John Worrall for their continuous support, encouragement as well as valuable comments on earlier drafts of this paper. Also to Paul Hoyningen-Huene for his perceptive comments on an early draft and to two anonymous referees, whose constructive criticism greatly improved the final form of this paper.

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Lefteris Farmakis.

Rights and permissions

Reprints and permissions

About this article

Cite this article

Farmakis, L. Did Tom Kuhn actually Meet Tom Bayes?. Erkenn 68, 41–53 (2008). https://doi.org/10.1007/s10670-007-9053-2

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s10670-007-9053-2

Keywords

Navigation