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Getting It Together: Psychological Unity and Deflationary Accounts of Animal Metacognition


Experimenters claim some nonhuman mammals have metacognition. If correct, the results indicate some animal minds are more complex than ordinarily presumed. However, some philosophers argue for a deflationary reading of metacognition experiments, suggesting that the results can be explained in first-order terms. We agree with the deflationary interpretation of the data but we argue that the metacognition research forces the need to recognize a heretofore underappreciated feature in the theory of animal minds, which we call Unity. The disparate mental states of an animal must be unified if deflationary accounts of metacognition are to hold and untoward implications avoided. Furthermore, once Unity is acknowledged, the deflationary interpretation of the experiments reveals an elevated moral standing for the nonhumans in question.

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Fig. 1
Fig. 2


  1. 1.

    Armstrong (1993: p. 93) also discusses this type of case. Discussing a case that parallels the driving case, Tye (2003: p. 2) imagines a distracted philosopher walking home thinking about her latest theory. She later realizes that she was not aware of any of her perceptions on the walk home. She sees (in some sense) the sidewalk and the trees (otherwise she would trip and bump into things), but lacks what Tye (2003: p. 5) calls “introspective consciousness” which seems to require a metacognitive ability. The distracted philosopher and the daydreaming driver are not introspectively aware of their perceptions (Tye 2003: p. 5). Yet they are conscious in some sense, as we discuss below.

  2. 2.

    Thanks to an anonymous reviewer for suggesting that we discuss in greater depth the notion of consciousness.

  3. 3.

    We think it is better to categorize consciousness into types, as with Tye (2003), rather than levels. Despite the utility of the concept of levels of consciousness in cognitive science, it faces conceptual difficulties and problems to do with properly ordering different types of global states (see Bayne et al. 2016).

  4. 4.

    Another test, for instance, is the so-called “false belief” test, constructed to ascertain when a child first learns to understand that the child’s beliefs are her own and may be different from others’ beliefs. We will focus exclusively on the uncertainty test.

  5. 5.

    In the experiments, the relevant key is marked “?” but we change the designation here only to aid our reader in interpreting Figs. 1 and 2.

  6. 6.

    References to Carruthers (2008) made by philosophers include Jacobson (2010) and Proust (2009, 2010), and references made by psychologists include Beran and Smith (2011), Couchman et al. (2009), and Smith (2009).

  7. 7.

    Folk psychology consists of the pre-theoretical assumptions people make about their own and others’ minds (Goldman 1993). Scientific progress is possible using folk psychology. The folk understand their own uncertainty in terms of conflicts between and among beliefs and desires. The subjects in the experiments, for example, desire to answer all questions in the way that brings reward but sometimes they do not know the right answer. When confronted with an ambiguous figure, the subject is unable to react quickly because of a paralyzing mismatch between their beliefs and desires. In folk psychology, therefore, the typical explanation of uncertainty is to say that the subject does not know on which belief they ought to act.

  8. 8.

    Morgan’s canon is a methodological principle used to guide the study of comparative psychology: “In no case may we interpret an action as the outcome of the exercise of a higher psychical faculty, if it can be interpreted as the outcome of the exercise of one which stands lower in the psychological scale” (Morgan 1894: p. 53). This requires that “the most general cognitive mechanism” (Karin-D’Arcy 2005: p. 182)—presumably not metacognition in the experiments discussed in this paper—be used to explain animal behavior. However, in a revised statement of the principle, Morgan cautions that the canon should not prohibit one from attributing more complex psychological processes if independent evidence suggests animals do undergo the more advanced process in question (for discussion, see Karin-D’Arcy 2005: p. 182). Grounding his view in Morgan’s canon, Carruthers (2008) holds that attributing more complex psychological processes is not necessary to explain animal behavior in the uncertainty tests since his first-order explanation is sufficient. We agree, provided the qualifications we advance in this paper. For cautions about the proper interpretation of Morgan’s Canon, see Sober (2009), Fitzpatrick (2008), Andrews and Huss (2014), and Andrews (2012).

  9. 9.

    Kant (1998: p. A103) discusses the need for the unity of consciousness in the process of counting.

  10. 10.

    Insofar as an animal’s beliefs and desires are unified in the relevant situations, this fact, if it is a fact, at least suggests that basic cognition feels to an animal no differently than basic cognition feels to us, when we are not metacognizing.

  11. 11.

    Whether Unity means that all contents of the metacognitive state must be globally broadcast in the brain or whether it applies only to the contents of specific modules is a matter we do not take up here.

  12. 12.

    Thanks to an anonymous reviewer for encouraging us to compare our notion of unity to others.

  13. 13.

    Not only must the two or more states be disposed to be accessed at time t1 (or between t1 and tn, for diachronic cases), but the subject must be disposed to access them at t1 (or during t1 through tn), in order for access to be possible.

  14. 14.

    The taxonomy of unity becomes more complicated if we combine the broader concepts of access unity and phenomenal unity with the different kinds of unity discussed above (object unity, spatial unity, etc.). These variations are not central to our argument.

  15. 15.

    Bayne and Chalmers (2003: p. 33, 46) are primarily interested in subsumptive phenomenal unity, in which a set of phenomenally conscious states are subsumed under a single phenomenal state.

  16. 16.

    If we can do this with monkeys, we can do it with humans. Hirstein (2012) argues for the possibility of mind-melding between humans, resisting the claim that the mind is necessarily private. The question arises whether such mind-melding creates an additional mind, a conclusion that seems virtually impossible to reach once Unity is firmly in place.

  17. 17.

    Although there are reasons to doubt the existence of levels of consciousness as a conceptual necessity or neuroscientific reality (Bayne et al. 2016), as mentioned in footnote 2, this need not contradict talk of “degrees” or “amount” of consciousness (or, conscious contents) for a specific type of consciousness (e.g., phenomenal, discriminatory, responsive), or to the total information processing occurring in the mind.


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We thank Dorit Bar-On for getting us started on this topic; Peter Carruthers for helpful criticisms when we presented at the 2017 University of Connecticut ECOM conference on “Human and Nonhuman Animals: Minds and Morals;” Irina Mikhalevich for comments at the 2016 Central APA meeting, as well as participants there; participants at the 2015 North Carolina Philosophical Society meeting, the 2014 Towards a Science of Consciousness Conference at the University of Arizona, and the 2013 Pacific University Northwest Philosophy Conference; and several anonymous reviewers.

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Correspondence to William A. Bauer.

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Comstock, G., Bauer, W.A. Getting It Together: Psychological Unity and Deflationary Accounts of Animal Metacognition. Acta Anal 33, 431–451 (2018). https://doi.org/10.1007/s12136-018-0340-0

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  • Metacognition
  • Psychological unity
  • Animal minds
  • Brainets
  • Moral standing of animals
  • Uncertainty test