Skip to main content
SpringerLink
Log in

What’s the matter with epistemic circularity?

  • Published:
Philosophical Studies Aims and scope Submit manuscript

Abstract

If the reliability of a source of testimony is open to question, it seems epistemically illegitimate to verify the source’s reliability by appealing to that source’s own testimony. Is this because it is illegitimate to trust a questionable source’s testimony on any matter whatsoever? Or is there a distinctive problem with appealing to the source’s testimony on the matter of that source’s own reliability? After distinguishing between two kinds of epistemically illegitimate circularity—bootstrapping and self-verification—I argue for a qualified version of the claim that there is nothing especially illegitimate about using a questionable source to evaluate its own reliability. Instead, it is illegitimate to appeal to a questionable source’s testimony on any matter whatsoever, with the matter of the source’s own reliability serving only as a special case.

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

Access this article

Log in via an institution

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

Instant access to the full article PDF.

Institutional subscriptions

Similar content being viewed by others

Notes

  1. The example is originally due to Vogel (2000). See also Alston (1986), Brueckner (forthcoming), Cohen (2002, 2005, 2010), Kornblith (2009), (Vogel 2008), (Weisberg 2010, —2012).

  2. Examples involving knights, knaves, and fools are loosely adapted from Smullyan (1978). Other examples of self-verifying and self-undermining sources can be found in Bergmann (2004), DeRose (1992), Elga and Egan (2005), Fumerton (1995), and Reid (1983, p. 276).

  3. A salient possibility here is rule circularity, which occurs when one vindicates the reliability of an inference rule in part by reasoning in accordance with that inference rule. In contrast to bootstrapping and self-verification procedures for vindicating the reliability of a source of information, it is an open question whether rule-circular vindications of inference rules are epistemically defective. See, e.g., Boghossian (2001), Dogramaci (2010), Van Cleve (1979), and (Vogel 2008).

  4. For one of the few, see Van Cleve (2003). See also Bergmann (2004), which offers a more qualified endorsement of some instances of bootstrapping.

  5. See Pryor (forthcoming) for a distinct but related use of the term ‘credulism’.

  6. A similar principle is discussed in Vogel (2008). See also Cohen (2002) and Van Cleve (2003) for discussion of a corresponding principle concerning knowledge rather than justified belief. Note that ‘prior’ refers to epistemic rather than temporal priority. See Pryor (2000, pp. 524–525) for a prominent discussion of the distinction. Without the requirement that one’s justification for believing the source is reliable be epistemically prior to one’s justification for believing that the source is reliable, Credibility Requires Apparent Reliability would be consistent with a view like Zalabardo (2005), which allows the source’s testimony itself to provide one’s justification to believe that the source is reliable.

  7. See Adler (2012) for a helpful review of recent work on the epistemology of testimony.

  8. Examples of antireductionist views include those advanced by Roush (2005), Titelbaum (2010), Vogel (2008), and Weisberg (2010). See Weisberg (2012, Sect. 2) for a helpful review.

  9. See, e.g., Weisberg (2010). No Feedback principle, Kallestrup (forthcoming) GEC, and Titelbaum (2010) and Pryor (MS, Sect. VII) ban on No-Lose Investigations.

  10. See note 8 above.

  11. See, e.g., Pryor (MS) and Wright (2004) for recent discussions of transmission failure.

  12. See Kallestrup (forthcoming) for a recent attempt.

  13. Avnur (2012) says that in special cases one can be committed to believing the consequences of one’s other beliefs without thereby being justified. It is natural to think that if one is committed to believing that p, then one is unjustified in adopting an attitude other than belief to p—in which case Avnur can be read as denying Existence. Jim Pryor has told me in conversation that he wishes to deny Deductive Closure by denying Existence.

  14. Vogel (2008) accepts (4) in the case of Roxanne, but denies a corresponding premises for cases involving basic inferential rules in the place of fuel gauge reading. Pryor (MS) does the same for perceptual cases. Weisberg’s (2010) account of bootstrapping lends itself most naturally to the denial of (4), although in response to an objection from White he allows for the possibility of denying (2) and with it Deductive Closure instead (see pp. 20–21). Kallestrup (forthcoming) denies a premise like (4) which concerns knowledge rather than justification, as does Kornblith (2009) for typical cases of bootstrapping.

  15. Although it does not affect the main thread of our discussion, it is arguable that Inductive Closure but not Deductive Closure must be amended to include a ‘no defeaters’ clause. Inductive Closure requires such an amendment because one might have a defeater for the conclusion of an inductive argument that does not defeat the premises. For example, I might have it on good authority that there is a black ball among those in an urn, and thus have a defeater for the conclusion that all the balls in the urn are white. Yet I still might know and be justified in believing that each of a large number of balls drawn so far has been white. In contrast, it is less obvious that Deductive Closure requires a ‘no defeaters’ clause, because one might think that any defeater for the conclusion of a single-premise deductive argument must also defeat the premise. (See Schechter 2013, however, for a dissenting view.) Even so, I think this potential difference between the inductive and deductive closure principles can be safely ignored, since no defeaters are present in the cases that concern us. (I furthermore take the addition of a ‘no defeaters’ clause to leave unaffected the motivation of Deductive Closure by the Existence thesis).

  16. I take this to be the guiding idea underlying rough and ready objections from White (2006, pp. 546–547) and Cohen (2010, p. 144).

  17. In 19,000 years, Roxanne will run 6,939,750 trials. The chance of a stunningly unreliable gauge giving incorrect readings on every trial will be 99.999999 %6,939,750, or just under 50 %.

  18. If the chance of a correct reading from an unreliable gauge is 1/5, then the chance of 10 correct readings in a row will be (1/5)10 = 99.99998976 %.

  19. See Christensen (2004) for a discussion with which I am largely sympathetic.

  20. A proposal in this vein is considered, but not endorsed, by Weisberg (2010, pp. 6–7).

  21. Supposing (conservatively!) that a reliable gauge stands a 99.9 % chance of giving a correct reading on a single trial, the chance of a reliable gauge giving 10 correct readings on 10 consecutive trials is 99.9 %10 = 99 %. If Roxanne’s believing a gauge’s reading means being as confident as one should be for a gauge that is known to be reliable, then probabilistic coherence requires a 99 % degree of confidence that the gauge has made no errors. It is plausible that if one is required to be 99 % confident then one is required to believe, but at any rate it is no more appealing to say that Roxanne is justified in being highly confident that the gauge has made no errors and is reliable than it is to say that she is justified in believing these things.

  22. The example has been adapted slightly from Weisberg (2010). As Wesiberg notes, a similar point is discussed in White (2006), who attributes it to Greg Epstein, Matt Kotzen, and Nico Silins.

  23. The name ‘expected reliability’ was arrived at independently by the author and White (2009), due to its similarity to ‘expected utility’.

  24. Proof: When you conditionalize on the fact that the source said that p, your justified posterior credence that the source’s testimony about p is correct will equal your justified prior credence iff

    1. (i)

      \( \Pr \left( {\left( {S(p) \wedge p} \right) \vee \left( {S(\neg p) \wedge \neg p} \right)\,|\,S(p)} \right) = \Pr \left( {\left( {S(p) \wedge p} \right) \vee \left( {S(\neg p) \wedge \neg p} \right)} \right). \)

    In the artificial cases under consideration, if your source does not say that p then it instead says that not-p. So iff (i),

    1. (ii)

      \( \Pr \left( {\left( {S(p) \wedge p} \right) \vee \left( {S(\neg p) \wedge \neg p} \right)\,|\,S(p)} \right) = \Pr \left( {\left( {S(p) \wedge p} \right) \vee \left( {S(\neg p) \wedge \neg p} \right)\,|\,S(\neg p)} \right). \)

    Iff(ii),

    1. (iii)

      \( \Pr \left( {\left( {S(p) \wedge p} \right)\,|\,S(p)} \right) = \Pr \left( {\left( {S(\neg p) \wedge \neg p} \right)\,|\,S(\neg p)} \right), \)

    or equivalently,

    1. (iv)

      \( \Pr \left( {p\,|\,S(p)} \right)\, = \,\Pr \left( {\neg p\,|\,S(\neg p)} \right). \)

  25. Even in a deterministic world, there surely is an important sense in which a double-headed coin stands a 100 % chance of landing heads, while fair coin stands a 50 % chance of landing heads. Arguably but plausibly, this can be understood in terms of the robustness of the coin’s landing heads in the face of minor variations in the initial conditions of the coin toss.

  26. Lewis (1980). A similar observation is made by White (2009).

  27. See note 24 above.

  28. A similar observation is made by White (2009, p. 243).

  29. Proof: Assume both the Parity Condition and the Lack of Bias Condition. Because the possibilities that the source says p and that the source says not-p are exhaustive,

    1. (v)

      \( \Pr \left( {S(p)\,|\,p} \right) = 1 - \Pr \left( {S(\neg p)\,|\,p} \right). \)

    and

    1. (vi)

      \( \Pr \left( {S(\neg p)\,|\,\neg p} \right) = 1 - \Pr \left( {S(p)\,|\,\neg p} \right). \)

    It follows from (v), (vi), and the Lack of Bias Condition that

    1. (vii)

      \( \Pr \left( {S(p)\,|\,\neg p} \right) = \Pr \left( {S(\neg p)\,|\,p} \right). \)

    From (vii), the Parity Condition, the Lack of Bias Condition, and the elementary theorems

    1. (viii)

      \( \Pr \left( {S(p)} \right) = \Pr \left( {S(p)\,|\,p} \right)\Pr (p) + \Pr \left( {S(p)\,|\,\neg p} \right)\Pr (\neg p) \)

    and

    1. (ix)

      \( \Pr \left( {S(\neg p)} \right) = \Pr \left( {S(\neg p)\,|\,p} \right)\Pr (p) + \Pr \left( {S(\neg p)\,|\,\neg p} \right)\Pr \left( {\neg p} \right), \)

    it follows that

    1. (x)

      \( \Pr \left( {S(p)} \right) = \Pr \left( {S(\neg p)} \right). \)

    And now we are a short step from the Neutrality Condition. From the Lack of Bias Condition and the definition of conditional probability, we have

    1. (xi)

      \( \frac{{\Pr \left( {S(p) \wedge p} \right)}}{\Pr (p)} = \frac{{\Pr \left( {S(\neg p) \wedge \neg p} \right)}}{\Pr (\neg p)}. \)

    From the Parity Condition and (v), we have

    1. (xii)

      \( \Pr \left( {S(p) \wedge p} \right) = \Pr \left( {S(\neg p) \wedge \neg p} \right). \)

    Finally, from (x) and (xii), it follows that

    1. (xiii)

      \( \frac{{\Pr \left( {S(p) \wedge p} \right)}}{{\Pr \left( {S(p)} \right)}} = \frac{{\Pr \left( {S(\neg p) \wedge \neg p} \right)}}{{\Pr \left( {S(\neg p)} \right)}} \)

    which is equivalent to the Neutrality Condition given the definition of conditional probability.

  30. Proof: It is an elementary theorem of the probability calculus that

    1. (xiv)

      \( \Pr \left( {S(p) \wedge p} \right) + \Pr \left( {S(\neg p) \wedge \neg p} \right) = \Pr \left( {\left( {S(p) \wedge p} \right) \vee \Pr \left( {S(\neg p) \wedge \neg p} \right)} \right). \)

    By algebra, we have:

    1. (xv)

      \( \frac{{\Pr \left( {S(p) \wedge p} \right)}}{\Pr (p)}\Pr (p) + \frac{{\Pr \left( {S(\neg p) \wedge \neg p} \right)}}{\Pr (\neg p)}\Pr (\neg p) = \Pr \left( {\left( {S(p) \wedge p} \right) \vee \Pr \left( {S(\neg p) \wedge \neg p} \right)} \right). \)

    From the definition of conditional probability, it follows that

    1. (xvi)

      \( \Pr \left( {S(p)\,|\,p} \right)\Pr (p) + \Pr \left( {S(\neg p)\,|\,\neg p} \right)\Pr (\neg p) = \Pr \left( {\left( {S(p) \wedge p} \right) \vee \left( {S(\neg p) \wedge \neg p} \right)} \right). \)

    From (xvi) and the Lack of Bias Condition, it follows that

    1. (xvii)

      \( \Pr \left( {S(p)\,|\,p} \right)\Pr (p) + \Pr \left( {S(p)\,|\,p} \right)\Pr (\neg p) = \Pr \left( {\left( {S(p) \wedge p} \right) \vee \left( {S(\neg p) \wedge \neg p} \right)} \right), \)

    and therefore that

    1. (xviii)

      \( \Pr \left( {S(p)\,|\,p} \right)\Pr (p) + \Pr \left( {S(p)\,|\,p} \right)\left[ {1 - \Pr (p)} \right] = \Pr \left( {\left( {S(p) \wedge p} \right) \vee \left( {S(\neg p) \wedge \neg p} \right)} \right). \).

    Simplifying terms then gives us (11).

  31. Proof: Because the possibilities that the source says p and that the source says not-p are exhaustive,

    1. (xix)

      \( \Pr \left( {S(\neg p)\,|\,\neg p} \right) = \left[ {1 - \Pr \left( {S(p)\,|\,\neg p} \right)} \right]. \)

    From (11) and the Lack of Bias Condition it follows that

    1. (xx)

      \( \left[ {1 - \Pr \left( {S(\neg p)\,|\,\neg p} \right)} \right] = \left[ {1 - \Pr \left( {\left( {S(p) \wedge p} \right) \vee \left( {S(\neg p) \wedge \neg p} \right)} \right)} \right]. \)

    We now have (12) from (xix) and (xx).

  32. For an overview of some findings from the social psychology literature along with philosophical reflection on those findings, see Elga (2005).

  33. Two minor notes are in order. First, I assume that A’s and B’s reliability are epistemically independent, in the sense that one of the source’s being a knight would not on its own amount to evidence concerning whether the other is a knight. Second, when A goes on to claim that A himself is a knight, his expected reliability will change, and so too will the credibility of his prior testimony that B is a knight.

  34. Although I do not wish to argue the historical point here, I take this skeptical challenge to be closely related to the traditional problem of the criterion. I thank Andrew Cling for pressing me to make this point explicit.

  35. See, e.g., Wright (2004).

  36. For a recent discussion, see Vogel (2005). An IBE response to perceptual skepticism along the lines suggested by Vogel could potentially be generalized to respond to skepticism about external sources of testimony, such as other people or fuel gauges. However, I think this strategy is less promising with respect to our faculties of memory and reasoning. For in the case of memory, one cannot judge that one’s apparent memories have been coherent in the past without employing one’s memories of their past coherence. And one cannot infer from the coherence of past reasoning-based judgments that reasoning is reliable without employing one’s faculty of reasoning, which I take to include the capacity for making inferences to the best explanation. It is not obvious that the IBE strategy’s failure to generalize to memory and reasoning undermines its plausibility as a response to perceptual skepticism, for it is not obvious that a response to skepticism ought to be uniform across different kinds of skeptical doubts. I hope to address these issues in greater depth in future work.

  37. Reid (1983, p. 276), also quoted in Plantinga (2002, p. 242).

  38. DeRose (1992).

  39. For the source’s claim that p to increase its expected reliability, p will have to selectively confirm an ad hoc collection of favorable and unfavorable hypotheses about its reliability. For example, suppose you know that the source is either 100 or 80 or 60 or 40 or 20 or 0 % reliable, with none more likely than another. If the source claims that it is either 100 or 80 or 0 % reliable, this will rule out that it is 0 % reliable, nudging its expected reliability up from 50 % to roughly 63 %.

  40. See Barnett (MS a).

  41. See Barnett (MS b, MS c).

References

  • Adler, J. (2012). Epistemological problems of testimony. In E. Zalta (Ed.), The Stanford encyclopedia of philosophy. Available at plato.stanford.edu/archives/fall2012/entries/testimony-episprob/.

  • Alston, W. P. (1986). Epistemic circularity. Philosophical Studies, 47, 1–28.

    Google Scholar 

  • Avnur, Y. (2012). Closure reconsidered. Philosophers’ Imprint, 12(9), 1–16.

    Google Scholar 

  • Barnett, D. J. (MS a). Knowledge, luck, and the Cartesian circle. Available at www.davidjamesbar.net.

  • Barnett, D. J. (MS b). Is memory merely testimony from one’s former self? Available at www.davidjamesbar.net.

  • Barnett, D. J. (MS c). The agony of higher-order defeat. Available at www.davidjamesbar.net.

  • Bergmann, M. (2004). Epistemic circularity: Malignant and benign. Philosophy and Phenomenological Research, 69(3), 709–727.

    Article  Google Scholar 

  • Boghossian, P. (2001). How are objective epistemic reasons possible. Philosophical Studies, 106(1/2), 1–40.

    Article  Google Scholar 

  • Brueckner, A. (forthcoming). Bootstrapping, evidentialist internalism, and rule circularity. Philosophical Studies.

  • Christensen, D. (2004). Putting logic in its place: Formal constraints on rational belief. New York: Oxford University Press.

    Book  Google Scholar 

  • Cohen, S. (2002). Basic knowledge and the problem of easy knowledge. Philosophy and Phenomenological Research, 65(2), 309–329.

    Article  Google Scholar 

  • Cohen, S. (2005). Why basic knowledge is easy knowledge. Philosophy and Phenomenological Research, 70(2), 417–430.

    Article  Google Scholar 

  • Cohen, S. (2010). Bootstrapping defeasible reasoning, and a priori justification. Philosophical Perspectives, 24, 141–159.

    Article  Google Scholar 

  • DeRose, K. (1992). Descartes, epistemic principles, epistemic circularity, and scientia. Pacific Philosophical Quarterly, 73, 220–238.

    Google Scholar 

  • Dogramaci, S. (2010). Knowledge of validity. Noûs, 44(3), 403–432.

    Article  Google Scholar 

  • Elga, A. (2005). On overrating oneself…and knowing it. Philosophical Studies, 123(1–2), 115–124.

    Article  Google Scholar 

  • Elga, A., & Egan, A. (2005). I can’t believe I’m stupid. Philosophical Perspectives, 19(1), 77–93.

    Article  Google Scholar 

  • Fumerton, R. (1995). Metaepistemology and skepticism. Lanham, MD: Rowman and Littlefield.

    Google Scholar 

  • Kallestrup, J. (forthcoming). Bootstrapping and rollback: Generalizing epistemic circularity. Synthese.

  • Kornblith, H. (2009). A reliabilist solution to the problem of promiscuous bootstrapping. Analysis, 69, 263–267.

    Article  Google Scholar 

  • Lewis, D. (1980). A subjectivist’s guide to objective chance. In R. Jeffrey (Ed.), Studies in inductive logic and probability (Vol. 2). Berkeley: University of California Press.

    Google Scholar 

  • Plantinga, A. (2002). Reply to Bielby’s cohorts. In J. Bielby (Ed.), Naturalism defeated?. Ithaca: Cornell University Press.

    Google Scholar 

  • Pryor, J. (2000). The skeptic and the dogmatist. Noûs, 34, 517–549.

    Article  Google Scholar 

  • Pryor, J. (forthcoming). Problems for credulism. In C. Tucker (Ed.), Seemings and justification: New essays on dogmatism and phenomenal conservatism. Oxford: Oxford University Press.

  • Pryor, J. (MS). Is Moore’s argument an example of transmission-failure. Available at http://www.jimpryor.net/research.

  • Reid, T. (1983). In R. E. Beanblossom & K. Lehrer (Eds.), Essays on the intellectual powers of man in inquiry and essays. Indianapolis: Hackett Publishing Company.

    Google Scholar 

  • Roush, S. (2005). Tracking truth: Knowledge, evidence, and science. Oxford University Press

  • Schechter, J. (2013). Rational self-doubt and the failure of closure. Philosophical Studies, 163(2), 428–452.

    Article  Google Scholar 

  • Smullyan, R. (1978). What is the name of this book?—The riddle of dracula and other logical puzzles. Englewood Cliffs, NJ: Prentice Hall International.

    Google Scholar 

  • Titelbaum, M. (2010). Tell me you love me: Bootstrapping, externalism, and no-lose epistemology. Philosophical Studies, 149(1), 119–134.

    Article  Google Scholar 

  • Van Cleve, J. (1979). Foundationalism, epistemic principles, and the Cartesian circle. Philosophical Review, 88, 55–91.

    Article  Google Scholar 

  • Van Cleve, J. (2003). Is knowledge easy—or impossible? Externalism as the only alternative to skepticism. In S. Luper (Ed.), The skeptics: Contemporary essays. Aldershot: Ashgate Publishing.

    Google Scholar 

  • Vogel, J. (2000). Reliabilism leveled. Journal of Philosophy, xcvii(11), 602–623.

    Article  Google Scholar 

  • Vogel, J. (2005). The refutation of skepticism. In M. Steup & E. Sosa (Eds.), Contemporary debates in epistemology. Malden, MA: Blackwell Publishing.

    Google Scholar 

  • Vogel, J. (2008). Epistemic bootstrapping. Journal of Philosophy, 105(9), 518–539.

    Google Scholar 

  • Weisberg, J. (2010). Bootstrapping in general. Philosophy and Phenomenological Research, 81(3), 525–548.

    Article  Google Scholar 

  • Weisberg, J. (2012). The bootstrapping problem. Philosophy Compass, 7(9), 597–610.

    Google Scholar 

  • White, R. (2006). Problems for dogmatism. Philosophical Studies, 131, 525–557.

    Article  Google Scholar 

  • White, R. (2009). On treating oneself and others as thermometers. Episteme, 6(3), 233–250.

    Article  Google Scholar 

  • Wright, C. (2004). Warrant for nothing (and foundations for free)? Supplement to the Proceedings of the Aristotelian Society, 78(1), 167–212.

    Article  Google Scholar 

  • Zalabardo, J. L. (2005). Externalism, skepticism, and the problem of easy knowledge. Philosophical Review, 114(1), 33–61.

    Article  Google Scholar 

Download references

Acknowledgment

The author is grateful for helpful comments from Paul Boghossian, Justin Clarke-Doane, Andrew Cling, Jonathan Cottrell, Sinan Dogramaci, Hartry Field, Don Garrett, Jesper Kallestrup, Colin Marshall, Tom Nagel, Jim Pryor, Stephen Schiffer, Sharon Street, Peter Unger, David Velleman, and the participants of the NYU dissertation seminar.

Author information

Authors and Affiliations

  1. Department of Philosophy, Union College, 807 Union St, Schenectady, NY, 12308, USA

    David James Barnett

Authors
  1. David James Barnett
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to David James Barnett.

Rights and permissions

Reprints and permissions

About this article

Cite this article

Barnett, D.J. What’s the matter with epistemic circularity?. Philos Stud 171, 177–205 (2014). https://doi.org/10.1007/s11098-013-0261-0

Download citation

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s11098-013-0261-0

Keywords

Search

Navigation