Belief-Forming Processes, Extended


We very often grant that a person can gain knowledge on the basis of epistemic artifacts such as telescopes, microscopes and so on. However, this intuition threatens to undermine virtue reliabilism according to which one knows that p if and only if one’s believing the truth that p is the product of a reliable cognitive belief-forming process; in an obvious sense epistemic artifacts are not parts of one’s overall cognitive system. This is so, unless the extended cognition hypothesis (HEC) is true. According to HEC when parts of the environment become properly coupled to the agent’s brain then they too can be considered constitutive parts of the overall cognitive mechanism—i.e. cognition potentially extends to the world surrounding the agent. Interestingly, HEC and the broader framework of virtue reliabilism share some intriguing similarities, which render these two views mutually supportive. Making these similarities explicit provides a principled account of the way in which our knowledge-conducive cognitive characters may extend beyond our natural cognitive capacities by incorporating epistemic artifacts.

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  1. 1.

    For a full account of how sensorimotor knowledge is constitutive of perception see (Noë 2004). “The basic claim of the enactive approach is that the perceiver’s ability to perceive is constituted (in part) by sensorimotor knowledge (i.e. by practical grasp of the way sensory stimulation varies as the perceiver moves)”. (Noë 2004, 12). “What the perception is, however, is not a process in the brain, but a kind of skillful activity on the part of the animal as a whole”. (Noë 2004, 2). “Perception is not something that happens to us or in us, it is something we do”. (Noë 2004, 1). Sensorimotor dependencies are relations between movements or change and sensory stimulation. It is the practical knowledge of loops relating external objects and their properties with recurring patterns of change in sensory stimulation. These patterns of change may be caused by the moving subject, the moving object, the ambient environment (e.g. changes in illumination) and so on.

  2. 2.

    See Bach-y-Rita and Kercel (2003) for a recent review on TVSS.

  3. 3.

    Hereafter, ‘virtue reliabilism’ will signify the view that the ability intuition on knowledge is only a necessary condition on knowledge whereas ‘robust virtue reliabilism’ is the view that the satisfaction of the ability intuition is both necessary and sufficient for knowledge. The idea that knowledge must be grounded in cognitive abilities can be traced back to the writings of Ernest Sosa (1988, 1993) and Alvin Plantinga (1993). For more recent advocacies see Greco (1999, 2004, 2007) and Pritchard (2009, 2010a, b, c). Pritchard, however, holds that the ability intuition is not the only guiding epistemological intuition and he thus avoids to formulate a version of robust virtue reliabilism. Instead he proposes a kind of anti-luck virtue reliabilism. See (Pritchard 2010a, b). See also ft. 11.

  4. 4.

    Another reason why Greco appeals to the notion of one’s cognitive character is his attempt to do away with the problem of the strange and fleeting processes. See (1999, 286–9).

  5. 5.

    Notice that Greco calls his view ‘agent reliabilism’. I have here preferred the alternative name ‘robust virtue reliabilism’ for two reasons. First, Greco himself does not explicitly endorse such a strong formulation of the ability intuition on knowledge. Instead, Greco holds that S knows that p if and only if S’s reliable cognitive character is an important—but not necessarily the most important—necessary part of the total set of causal factors that give rise to S’s believing the truth regarding p (see Greco 1999, 287–8; 2004, 123; 2010,12). (However, his critics argue that he implicitly endorses a strong version of robust virtue reliabilism along the lines of the above formulation. See (Lackey 2008) and (Vaesen 2010). See also (Kelp 2011)). Second, I wanted to make explicit that this approach falls under the broader trend of virtue epistemology, “since the stable and successful dispositions of a person are appropriately understood as virtues” (Greco 1999, 287).

  6. 6.

    See (Gettier 1963). As an anonymous referee has noted, familiar Gettier cases can be addressed by process reliabilism, so why the need for the virtue theoretic element? There are, however, Gettier cases such as the Temp case (see section four) where while one’s way of forming beliefs is reliable, it is not responsive to the facts, but the other way around. If, however, one’s belief-forming process is a cognitive ability, then one’s beliefs are formulated in a way that will guarantee their responsiveness to the facts; hence the need for strengthening process reliabilism by accommodating the ability intuition on knowledge.

  7. 7.

    Notice, here, that the claim is that the cognitive success must be the product of a reliable cognitive belief-forming process. It is not the weaker claim that cognitive ability must have been involved in the acquisition of one’s true belief, since this can be satisfied far too easily in ways that do not exclude luck.

  8. 8.

    The Barney case is described in Goldman (1976) and credited to Carl Ginet. This formulation of the example is due to Pritchard (2009, 12).

  9. 9.

    The sensitivity principle is usually formulated as follows: If S knows that p, then S’s true belief that p, is such that, had p been false, S would not have believed p. The classic defenses of the sensitivity principle can be found in Dretske (1970) and Nozick (1981). The safety principle is usually understood thusly: if S knows that p, then S’s true belief that p, is such that S’s belief that p could not have easily been false. For recent defenses of the safety principle see Sosa (1999, 2000) and Pritchard (2002, 2008). For a very good discussion concerning the relation between the ability and the anti-luck intuition on knowledge see Pritchard (2010a).

  10. 10.

    Notice, however, a subtle difference: In regular Gettier cases, the knowledge-undermining luck is very direct, in that the luck concerns the relationship between the belief and the fact. One’s belief is erroneously formed but there is a lucky fact that renders it true. Luck intervenes between the belief and the fact. On the contrary, in cases like the one Barney is in, the knowledge-undermining luck is quite indirect; indeed, it is specifically environmental. Barney does look at a real barn and believes that there is a real barn in front of him. There is nothing wrong with the way he forms his belief. However, given the environmental conditions he cannot acquire knowledge in this way. Luck interferes with the environment in such a way that even a well-formed belief will be a lucky one if true. So, it seems that while the ability condition on knowledge can deal with the normal (non-environmental) knowledge-undermining epistemic luck involved in Gettier cases, it may not be able to deal specifically with environmental knowledge-undermining luck.

  11. 11.

    Consider for example Anti-Luck Virtue Epistemology: S knows that p if and only if S’s safe belief that p is the product of her relevant cognitive abilities (such that her safe cognitive success is to a significant degree creditable to her cognitive agency) (Pritchard 2010a, 20). Again, in (Pritchard 2010b, 76) we can read: “knowledge is safe belief that arises out of the reliable cognitive traits that make up one’s cognitive character, such that one’s cognitive success is to a significant degree creditable to one’s cognitive character”. Notice, however, that Greco (2007, 2008) has put forward a ‘subject-sensitive, interest-dependent’ contextualism for judging which belief-forming processes are reliable each time that may successfully deal with the Barney and similar cases, thereby avoiding the need for an explicit anti-luck component in a complete account of knowledge.

  12. 12.

    The Jenny case is adapted from Jennifer Lackey’s ‘Morris case’ (2007, 352). This formulation of the example is due to Pritchard (2009, 68). Apart from the hero’s name, however, nothing else really changes.

  13. 13.

    For more details on the Jenny case, see (Pritchard 2010a, 18).

  14. 14.

    Traditionally, accounts of testimonial knowledge are divided in two main trends. The first one is called reductionism and it is the view that a hearer is justified in believing a speaker’s testimony if and only if she has non-testimonial positive reasons in favor of the speaker’s reports, such that her justification for accepting them is reducible to basic sources of knowledge such as sense perception, memory and inductive inference. It is often thought that Hume was committed to a form of reductionism (Hume 1977). Contemporary proponents of the view include Faulkner (2000) and Fricker (1994). The second trend is called non-reductionism and it is the view that one is by default justified in believing one’s testimony unless one has negative reasons for doing so. On this view, testimonial justification cannot or need not be reduced to more basic sources of knowledge. Reid (1983) is thought to be the first to defend the view. Contemporary proponents of non-reductionism on testimonial knowledge are, amongst others, Burge (1993), Weiner (2003) and Audi (1998). Recently, however, Jennifer Lackey (2008) has put forward a dualist account of testimonial knowledge, which accommodates both of the aforementioned views.

    (Robust) virtue reliabilism appears to accord only with reductionism on testimonial knowledge, due to its strong demand that the cognitive success should be primarily creditable to the hearer’s cognitive character.

  15. 15.

    Thanks to an anonymous referee for pressing this point.

  16. 16.

    Provisionally this point may seem ambiguous but it will hopefully become clearer in the discussion of section three where I explore the phenomenon of continuous reciprocal causation between the organismic agent and the epistemic artifact.

  17. 17.

    Notice, then, that the cognitive success being primarily creditable to one’s cognitive agency and it being the product of cognitive abilities is not exactly the same thing. That is, one’s cognitive success can be the product of one’s cognitive abilities even if it is not primarily creditable to one’s cognitive agency.

  18. 18.

    Pritchard makes this point in (2010c, 137; en. 7). Although this might generally be a good way to start judging whether a process can count as a bona fide cognitive ability, notice that Pritchard uses the terms ‘cognitive agency’ and ‘cognitive character’ interchangeably thereby running the risk of rendering his criterion circular or at least unsafe. As I argue in section five, where I discuss several thought experiments, Pritchard has indeed been led astray by his criterion with respect to the Temp case. Therefore, we are in need of an alternative way to judge whether a process has been appropriately integrated within one’s cognitive character. I offer one in section four.

  19. 19.

    That is, even though we might be epistemologically motivated to accept the employment of artifacts as bona fide cognitive abilities, such a claim would be very weak in the absence of any metaphysical support.

  20. 20.

    Parity Principle: “If as we confront some task, part of the world functions as a process which, were it done in the head, we would have no hesitation in recognizing as part of the cognitive process, then that part of the world is (so we claim) part of the cognitive process” (Clark and Clalmers 1998, 8). Parity principle is only meant as an intuition pump in order to overcome internalist prejudices, when judging whether external processes could in principle be parts of one’s overall cognitive system. Many critics, however, have given much stronger interpretations that generate counterintuitive results. For a very good discussion on the objections raised against the Parity Principle see (Menary 2007, 2010a, b).

  21. 21.

    For a short discussion of most of these objections see (Menary 2006).

  22. 22.

    I am thankful to an anonymous reviewer for pointing out that the above point might be interpreted as an epistemic argument for HEC; in short, that HEC is true because we must consider the contribution of external materials if we are to fully understand human cognition. This is a clearly fallacious argument but it is just a misinterpretation. My point is rather conceptual: since the best available mathematics (i.e. conceptual tools) we have in order to model systems that exhibit CRC postulate a further coupled (extended) system, we should accept the hypothesis of extended cognition as true.

    As Julian Kilverstein has noted in personal communication, however, the same point may be interpreted as a metaphysical one, concerning the nature of the systems involved in cases of CRC. As Varela writes: "If one says there is a machine M in which there is a feedback loop through the environment, so that the effects of its output affect its input [i.e. M reciprocally interacts with some environmental aspect], one is in fact talking about a larger machine M′ which includes the environment and the feedback loop in its defining organization” ((Varela 1979, 158), quoted by Hurley (1998, 404)). The reason is that the effects of the environment on M are partly defined by M’s ongoing states and vice versa. This dense and complex interaction amounts to an overall behavior which is in fact internal to a larger system M′ comprising of both M and the relevant environmental aspect.

  23. 23.

    For the importance of the normative aspects of the external representational systems in understanding cognition see (Menary 2007).

  24. 24.

    For a discussion on Clark’s view regarding language see (Wheeler 2004). For a straightforward criticism, see (Rupert 2010).

  25. 25.

    But if one allows for such an understanding of public language and text, then important conceptual space is created to lengthen the list of epistemic artifacts in interesting ways. For, as Robert Logan (2003, 275) claims, “speech, writing, math, science and computing form an evolutionary chain of languages. Each of these activities can be considered as a separate language because each allows us to think differently, create new ideas and develop new forms of expression. Another consideration is that each of these five forms of language possesses its own unique semantics and syntax and hence qualifies as a language in itself according to criteria set by classical linguistics”. While much more remain to be said on this matter, concentrating on the case of scientific theories, it is interesting that philosophers of science such as Imre Lakatos write: “[scientists] use our most successful theories as extensions of our senses” (Lakatos 1970, 107, emphasis in the original). Given the appropriate theorizing, however, this may turn out to be more than just a metaphor. That is, it could be the case that scientific theories, like public language and text, are software epistemic artifacts that extend one’s cognitive abilities beyond one’s natural cognitive capacities.

  26. 26.

    This paper has been available online since 2006, but it was first published in 2010 in The Extended Mind, ed. Menary. Cambridge: MIT press

  27. 27.

    In (Clark and Chalmers 1998, 17) the authors consider a further criterion: “Fourth, the information in the notebook has been consciously endorsed at some point in the past, and indeed is there as a consequence of this endorsement”. However, as the authors further note, “the status of the fourth feature as a criterion for belief is arguable (perhaps one can acquire beliefs through subliminal perception, or through memory tampering?)”, so they subsequently drop the said criterion.

  28. 28.

    Notice that, as the above quote suggests, Clark treats CRC only as a sufficient condition on cognitive extension. Given, however, that CRC not only helps to overcome several problems for the hypothesis of extended cognition, but it also helps to distinguish the view from rival alternative theories (i.e. from HEMC, see also footnote 30) that might allegedly offer the same causal-explanatory accounts for a given phenomenon, I wish to accentuate its importance by treating it as a necessary condition on cognitive extension.

  29. 29.

    For more details see (Van Gelder 1995, 355–8, 373). See also ft. 20.

  30. 30.

    An anonymous referee has pointed out that the HEMC theorist may be happy to accept that an agent might be in a continuous and reciprocal causal relation with some aspect in the environment, but still deny cognitive extension. However, this seems not to be an option for the HEMC theorist because given the conceptual framework of Dynamic Systems Theory, in such cases, HEMC collapses into HEC. In fact, Rupert, in chapter 7 of his book (2009), concedes that Dynamic Systems Theory can provide strong support to the hypothesis of extended cognition in just the way I have been here describing (Rupert 2009, 131–4). It is telling that none of the dynamic models that he considers in favor of HEMC concerns a two-way interaction between the organism and some environmental aspect. For more details see (Rupert 2009, 137–149).

  31. 31.

    Adams and Aizawa (2008) claim that the mark of the cognitive is the manipulation of representations with underived content, which is plausibly not a feature of any external process, and they thus avoid begging the question against externalism when they put forward the causal-constitution fallacy. However, it is not clear what Adams and Aizawa have in mind and how the said criterion is supposed to promote internalism. Thus a long debate has been generated. Indicatively, see (Clark 2008), (Clark 2010b), (Menary 2006), (Adams and Aizawa 2010), (Ross and Ladyman 2010).

  32. 32.

    Notice, however, that both hypotheses may turn out to be successful, though HEMC might be so only with respect to more mundane cases.

  33. 33.

    That is, the process does not need to be, due to any underlying logical or quasi-logical relations, 100% reliable. Memory, for example, is supposed to be reliable even though one may misremember, and so it is only contingently reliable.

  34. 34.

    The idea here is that trustworthiness (i.e. being regarded as reliable) might sometimes supervene on values other than objective reliability (i.e. the tendency to lead to success rather than failure). See the next footnote for a description of just such a case.

  35. 35.

    To elaborate a bit more on this point, an anonymous referee has objected that in the United States, there are many individuals who trust a particular cable TV “news organization”, but this news organization often provides misleading information. Viewers of this cable TV “news” channel trust this medium, but it is not reliable in the epistemologist’s sense. So, it may now appear that Clark’s conditions and the epistemologist’s reliability condition come apart. In response, let me draw your attention to two points. First, as noted above, Clark’s claim that in order for something to be trustworthy it must not usually be subject to critical scrutiny implies that the agent would check the object of his trust on the face of discrepancies. In contrast, the viewers of the American TV news channel appear that they would not, and this is a kind of blind trust that is quite different from the kind of trust Clark has in mind. Accordingly, the fact that there might be kinds of trust that have nothing to do with objective reliability, should not generate any problems for the identification of Clark’s ‘trustworthiness’ condition with the epistemologist’s objective reliability criterion.

    Second, even if on Clark’s account, the American TV “news” channel were to count as part of one’s cognitive economy—were it to also satisfy the rest of the criteria for cognitive extension—one could note that this is an issue about which epistemology and philosophy of mind can, and should exchange normative considerations. That is, even if, when philosophizing about what may count as part of an agent’s mind, we do not focus on the nature of a good mind, epistemology could point out that a conscientious mind should try to believe what is true and thereby employ the resources, which are reliable in the epistemologist’s sense. Nevertheless, Clark seems to accommodate this normative dimension of the mind through his “not-usually-subject-to-critical-scrutiny” understanding of trustworthiness, thus having been in line with the reliabilist tradition in epistemology, all along.

  36. 36.

    (Pritchard 2009, 48)

  37. 37.

    Adapted from Pritchard (2010c, 136) who attributes it to Plantinga (1993).

  38. 38.

    Notice that Alvin’s lesion is not one of the belief-forming processes he would employ was he motivated to believe the truth. Or, in other words, forming beliefs on the basis of the brain lesion cannot be deemed trustworthy. Alvin cannot automatically endorse the products of this process; it’s not the case that, from Alvin’s ‘point of view’, the resource is not usually subject to critical scrutiny simply because it is a recently acquired one.

  39. 39.

    Recall that according to Pritchard when some cognitive success is significantly creditable to one’s cognitive agency, then the belief-forming process by which the belief was acquired can be said to have been appropriately integrated within one’s cognitive character.

  40. 40.

    Notice, then, that while it is the case that whenever CRC takes place the cognitive success will be significantly creditable to one’s cognitive agency, things do not work the other way around.

  41. 41.

    That is, in being aware of the facts, Alvin has surely deemed his belief-forming process reliable and, as time goes by, it can start being one of his dispositions/habits.

  42. 42.

    Put another way, Tempo has acquired knowledge of the sensorimotor contingencies that accompany his continuous interaction with the device.


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I am grateful to Andy Clark, Julian Kilverstein, Duncan Pritchard and two anonymous reviewers for the Review of Philosophy and Psychology for feedback to previous drafts. I am also thankful to Shane Ryan and Eusebio Waweru for drawing my attention to useful corrections.

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Palermos, S.O. Belief-Forming Processes, Extended. Rev.Phil.Psych. 2, 741–765 (2011).

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  • True Belief
  • Cognitive Agency
  • Gettier Case
  • Cognitive Success
  • Testimonial Knowledge