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Mental Time Travel and Disjunctivism

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The paper discusses radical constructivism about episodic memory as developed by Kourken Michaelian under the name of “simulationism”, a view that equates episodic memory with mental time travel. An alternative, direct realist view is defended, which implies disjunctivism about the appearance of remembering. While admitting the importance of mental time travel as an underlying cognitive mechanism in episodic memory, as well as the prima facie reasonableness of the simulationist’s critique of disjunctivism, I formulate three arguments in defense of disjunctivism, which thus appears to be a feasible alternative to radical constructivism.

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  1. Though the idea of generativity is commonplace in psychology, initially MODCON was considered an iconoclastic view in philosophy. Lately, however, more and more philosophers subscribe to it (e.g. Dokic 2001; Lackey 2005; Matthen 2010; Michaelian 2011). RADCON is truly radical, and I am only aware of Michaelian 2016a where it is explicitly defended, though Fernandez 2018 puts forward a functionalist theory of episodic remembering which seems to imply that RADCON is correct. More exactly, Fernandez’s role functionalism about remembering is the view that for any subject S and event e, S remembers e just in case S has some mental image i that satisfies what Fernandez calls the “mnemonic role”, namely: i tends to cause in S a disposition to believe both that e happened and that S experienced e to happen, and i tends to be caused in S by having experienced e to happen (Fernandez 2018: 64). The causal conditions on i (that is, on imagery) states a tendency, not an actual cause. This is similar to Michaelian’s condition on remembering which states that the current mental state tokened when episodically remembering the past is brought about by a system that reliably generates content that matches events experienced in the past.

  2. One might also interpret sense datum theory as affirming directness since sense data are primary objects of subjective acquaintance. I prefer to interpret it as involving indirect access to the perceptual objects, because, contrary to our naïve beliefs, according to sense datum theory we are not related to material objects, but to ideal ones constructed out of sense data.

  3. For a defense of sense datum theories, see Howard Robinson 1994.

  4. Classic proposals and defenses are Elizabeth Anscombe 1965 and David Armstrong 1968: ch, 11. The stronger, recent view that representational properties determine phenomenal ones in perception is defended, among others, in Alex Byrne 2001. The stronger view is not essential to hold for an intentionalist about perception.

  5. For a rich analysis and defense of adverbialism, see Michael Tye 1984.

  6. I address this problem in Aranyosi 2020. The best account of what direct realism about memory should look like is in Dorothea Debus 2008.

  7. I should note that there is an analogous problem in perception when it comes to the issue of time, namely, that there is always a time lag between when the visual information is emitted (by photon reflection/absorption) by an object and when it reaches our eyes. It is quasi-immaterial when we perceive close enough objects, but it becomes a problem for direct realists when we perceive extremely distant ones, such as stars. It is not the place here to dedicate a proper discussion to this time-lag argument against direct realism, propounded by Bertrand Russell (1948: 217), but it will suffice to note that whereas awareness of a time-lag in perception comes to surface in special circumstances (viz. with objects an astronomical distances), such a time lag is ubiquitous in memory. Hence, it is an immediate apparent quandary in the case of direct realism about memory. Thanks to an anonymous referee for asking me to address this issue.

  8. It is important to emphasize that it is worldly contents, that is, bits of concrete reality that enter this relation according to genuine direct realism. Tufan Kıymaz raised with me the issue of whether one could be direct realist about memory but intentionalist about perception. At first sight it seems so, but further inspection reveals that such a position would not be genuinely direct realist about memory. It would simply be equivalent to a classical preservationist view, according to which it is a mental representation of a perceived event that gets preserved and then retrieved when we remember. A further worry, expressed by one the referees of this paper, is that under such a view, memory representations depend on a previous mode of access to the relevant events or objects, and it is hard to see how an indirect mode of access to something could give rise to a more direct mode of access to it at a later time.

  9. Recent discussion include Burge 2005, Byrne 2009, Smith 2010.

  10. The disjunctive analysis was to be embraced and further elaborated much later by a number of authors, in works related to the problems of perception, such as Snowdon 1990, 2008, McDowell 1982, 1986, Martin 2002, 2004, 2006, Campbell 2002, Byrne and Logue 2008.

  11. A referee asks why I think that episodic memory and imagination are similar; I myself do not think so, but for the sake of this paper’s arguments I follow Michaelian, who does think that memory is episodic imagination of the past (cf. Michaelian 2016a: ch 6, especially section 10.).

  12. Again, to reply to a referee’s objection to this similarity in phenomenology, the key element here is “the past”. Remembering, according the simulationist, is episodically imagining the past. The referee correctly points out that Michaelian does include a metacognitive feeling of pastness in his analysis of remembering, but that does not change his view that remembering is a kind of imagination – imagination with a feeling of pastness.

  13. Michaelian is not alone in this misinterpretation of what disjunctivism is about. In the perception literature, Howard Robinson (1985: 173–177) commits the same error when advertising an argument against disjunctivism based on empirical discoveries about the proximate neural cause of one’s experience, namely, the discovery that this cause is common to perception and hallucination. Similarly, Tyler Burge (2005) appeals to empirical facts about vision in order to reject disjucntivism.

  14. It is worth noting that the causal theory fares better on this count since it (correctly) classifies non-veridical “memories” as non-memories, because they lack the right causal connection to the represented event. In other words, the causal theory is similar, as far as this point is concerned, to direct realism (and hence disjunctivism); the difference lies in the latter requiring a constitutive relation rather than (only) a causal one to account for the veridicality, and hence for the nature of memory qua memory.

  15. An anonymous referee has raised doubts about whether the causal theory of memory would be affected by the constructivist argument from unity and continuity, stating that the causal theory might be taken as analogous to representationalism in the literature on perception. This second claim –viz. that the right perceptual analog of the causal theory of memory is representationalism/intentionalism—is not correct. The right analog is the causal theory of perception, which was defended by H. P. Grice (1961) and P. F. Strawson (1979) several decades before any intentionalist theory of perception was formulated. The first claim –viz that it is doubtful that the causal theory of memory is analogous to disjunctivism in positing a fundamental difference between remembering the past and imagining it—the referee does have a point even if the right analog is the causal theory of perception. There is disagreement in the perception literature about whether the disjunctive analysis is compatible with the causal theory; in other words, about whether the causal theory is an instance of the highest common factor view. Snowdon (1981), for instance, thinks they are incompatible, whereas Child (1992) argues that they are. I follow the original proponents of the causal theory of perception, Grice and Strawson, in taking the causation as part of the concept of perception. More to the point, a causalist definition of seeing, for instance, is: Necessarily, subject S sees object o if, and only if, o causes in S the state of affairs of it looking to S as if φo.

  16. To be clearer, Michaelian, especially in his 2016b and 2018, thinks of remembering as a psychological process of content generation, which then he subdivides into veridical and nonveridical, depending on whether it matches the past episodes to a sufficient degree. The simulationist conditions on veridical remembering are (a) reliability (that is, the property of a process to generate content that usually tracks the past episodes), and (b) accuracy (that is, a high enough degree of matching the details of the past episode. Both (a) and (b) are satisfied by my example in the opening paragraph of this essay: my imagining our departmental meetings is reliable since I have a vast experience with them, and it is, ex hypothesi, accurate.

  17. This is also a response to an anonymous referee who was wondering whether I am not uncharitable to Michaelian by stating that he is committed to the idea that a representation of the past is an episodic memory only when its content is part of the personal past. Indeed, after stating the definition quoted above, Michaelian keeps explicitly mentioning this point in his book.

  18. Another anonymous referee had similar doubts about whether Michaelian’s formulation of the simulationist necessary and sufficient conditions, i.e. that there is merely a representation of the personal past rather than a veridical representation of it, really has the implication that I claim it has. Again, the problem is with the formula “personal past”, which is notoriously problematic, as witnessed in the literature on personal identity, where the so-called psychological criterion of personal identity over time is formulated (by John Locke initially) as a memory criterion, that is, in terms of the later person’s remembering the earlier person’s past. The criterion involves circularity since the concept of remembering already presupposes that of personal identity (you can’t remember someone else’s past). In our context, this formula is problematic in that it is hard to see what else is gained by adding the adjective “personal” to “imagining the past” than a condition of veridicality. There Is a big difference between saying “I am imagining the past” and “I am imagining my past”. Adding “my” changes the situation from a mere representation of a past episode to a veridical representation of it; see also below for how Michaelian fails to offer an analysis of the phrase “personal” except what he takes to be an “intuitive” understanding as a past in which one was involved.

  19. Or, indeed, as Bill Wringe pointed out to me, fully asleep, for all we learn from Michaelian’s notion of “being involved in an episode”.

  20. Michaelian does distinguish cases of remembering from cases of MTT merely matching the past facts accidentally (2016a: 109), which he explains via a malfunctioning and hence unreliable memory system. But note that in my examples the system is not malfunctioning and it is reliable: observing Bill at departmental meeting over the years made it possible for me to use imagination as a reliable way of retrodicting what he must have said at the latest meeting, even though I was absent, absent-minded, or sleepy, etc. It is a classical example of pure imaginative construction or content generation with no anchor (such as causal) in the past facts.

  21. This was in essence Thomas Reid’s direct realist view about memory. Reid stated this idea of basicness in theological terms: “I think it appears, that memory is an original faculty, given us by the Author of our being, of which we can give no account, but that we are so made.” (Bennett 2017: 134).

  22. –Which is different from, e.g., Debus’s (2008), in that I defend an interpretation of memory as a quasi-perceptual state, that is, I take the analogy with perception at face value and apply the direct realist recipe to memory.

  23. This is the reason why, in section 1, I said that the argument from hallucination in the perception literature is more relevant as an analog for similar problems in the theory of memory than the argument from illusion. Whereas, say, the visual appearance of a stick half-submerged in water as a bent stick is considered an illusion, therefore, a case of misperception, a memory of the same stick as having been perceived as straight is probably not considered to be a case of misremembering, as it is accurate enough for most purposes and in most contexts. This at least is my intuition. Nothing hinges on this, however, as far as this essay is concerned.

  24. Lewis uses an example of Karl Popper’s (1956) of a spherical wavefront expanding outwards from a point source – of the kind that forms, for example, when you throw a rock into a lake. Each point of the wave postdetermines what happened at the point at which the wave is emitted (e.g. that a rock has been thrown into the lake). This reverse process, which can be seen as a massive overdetermination of the source event, though not against the laws of nature, seldom happens in actual fact. Our universe is de facto asymmetric when it comes to causation: causes have a multitude of independent effects, but it seldom happens that a multitude of independent causes have the same effect. This asymmetry of causation, then, can be taken as grounding the asymmetry of time.


  • Addis, D.R., A.T. Wong, and D.L. Schacter. 2007. Remembering the past and imagining the future: Common and distinct neural substrates during event construction and elaboration. Neuropsychologia 45 (7): 1363–1377.

    Google Scholar 

  • Anscombe, G.E.M. 1965. The intentionality of sensation: A grammatical feature. In Analytical philosophy: First series, ed. R.J. Butler, 143–158. Oxford: Blackwell.

    Google Scholar 

  • Aranyosi, I., 2020, ‘Preteriception: Memory as past-perception’, manuscript.

  • Armstrong, D.M. 1968. A materialist theory of the mind. London: Routledge and Kegan Paul.

    Google Scholar 

  • Bennett, J. (ed.), 2017, Early modern texts. Thomas Reid, Essays on the Intellectual Powers of Man,

  • Bernecker, S. 2008. The metaphysics of memory. Berlin: Springer.

    Google Scholar 

  • Burge, T. 2005. Disjunctivism and perceptual psychology. Philosophical Topics 33 (1): 1–78.

    Google Scholar 

  • Byrne, A. 2001. Intentionalism defended. Philosophical Review 110: 199–240.

    Google Scholar 

  • Byrne, A. 2009. Experience and content. The Philosophical Quarterly 59 (236): 429–451.

    Google Scholar 

  • Byrne, A. and H. Logue, 2008, ‘Either/or’. In A. Haddock and F. Macpherson (eds.) Disjunctivism: Perception, Action, Knowledge, Oxford: Oxford University Press, 57–94.

  • Campbell, J. 2002. Reference and consciousness. Oxford: Oxford University Press.

    Google Scholar 

  • Child, W. 1994. Causality, interpretation, and the mind. Oxford: Clarendon Press.

    Google Scholar 

  • Crane, T. 2006. Is there a perceptual relation? In Perceptual Experience, ed. T. Gendler Szabó and J. Hawthorne, 126–146. Oxford: Oxford University Press.

    Google Scholar 

  • Debus, D., 2008, ‘Experiencing the past: A relational account of recollective memory’, dialectica 62 (4): 405–432.

  • Debus, D. 2014. “Mental time travel”: Remembering the past, imagining the future, and the particularity of events. Review of Philosophy and Psychology 5 (3): 333–350.

    Google Scholar 

  • Dokic, J. 2001. ‘Is memory purely preservative?’. In C. Hoerl and McCormack, T. (eds.) Time and Memory, Oxford: Oxford University Pres, 213–232.

  • Fernandez, J. 2018. The functional character of memory. In New directions in the philosophy of memory, ed. K. Michaelian, D. Debus, and D. Perrin. New York: Routledge.

    Google Scholar 

  • Grice H. P., 1961, ‘The causal theory of perception’, Proceedings of the Aristotelian Society, Supp. Vol. xxxv: 121–53.

  • Hinton, J.M. 1973. Experiences. Oxford: Clarendon Press.

  • Lackey, J. 2005. Memory as a generative epistemic source. Philosophy and Phenomenological Research 70: 636–658.

    Google Scholar 

  • Lewis, D. 1979. Counterfactual dependence and time's arrow. Noûs 13: 455–476.

    Google Scholar 

  • Martin, C.B., and M. Deutscher. 1966. Remembering. Philosophical Review 75: 161–196.

    Google Scholar 

  • Martin, M.G.F. 1997. The reality of appearances. In Thought and Ontology, ed. M. Sainsbury, 81–106. Milan: FrancoAngeli.

  • Martin, M.G.F. 2002. The transparency of experience. Mind and Language 17: 376–425.

    Google Scholar 

  • Martin, M.G.F. 2004. The limits of self-awareness. Philosophical Studies 120: 37–89.

    Google Scholar 

  • Martin, M.G.F. 2006. On being alienated. In Perceptual Experience, ed. Tamar S. Gendler and John Hawthorne, 354–410. Oxford: Oxford University Press.

    Google Scholar 

  • Matthen, M. 2010. Is memory preservation? Philosophical Studies 148: 3–14.

    Google Scholar 

  • McDowell, J. 1982. Criteria, defeasibility and knowledge. Proceedings of the British Academy 68: 455–479.

    Google Scholar 

  • McDowell, J., 1986, ‘Singular thought and the extent of inner space,’ in Philip Pettit and John McDowell (eds.), Subject, Thought and Context, Oxford: Clarendon Press.

  • Michaelian, K. 2011. Generative memory. Philosophical Psychology 24 (3): 323–342.

    Google Scholar 

  • Michaelian, K. 2016a. Mental time travel. Episodic memory and our knowledge of the personal past. Cambridge: MIT Press.

    Google Scholar 

  • Michaelian, K. 2016b. Confabulating, misremembering, relearning: The simulation theory of memory and unsuccessful remembering. Frontiers in Psychology 7: 1857.

    Google Scholar 

  • Michaelian K. and S. Robins, 2018, ‘Beyond the causal theory? Fifty years after Martin and Deutscher’, in K. Michaelian, D. Debus & D. Perrin (eds.), New Directions in the Philosophy of Memory. Routledge. pp. 13–32.

  • Michaelian K. 2018, ‘Confabulating as unreliable imagining: In defence of the simulationist account of unsuccessful remembering.’ Topoi. Online ahead of print. Special issue: Philosophical perspectives on confabulation. S. Stammers and L. Bortolotti (Eds.) DOI:, 39, 133, 148.

  • Nanay, B. 2016. Philosophy of perception: A road map with lots of bypass roads. In Current controversies in philosophy of perception, ed. B. Nanay. London: Routledge.

    Google Scholar 

  • Nudds, M. 2009. Recent work in perception: naïve realism and its opponents. Analysis 69: 334–346.

    Google Scholar 

  • Perrin, D., 2016, ‘Asymmetries in subjective time’, in Michaelian, Klein, & Szpunar 2016d: 39–61.

  • Popper, K. 1956. The arrow of time. Nature 1777: 538.

    Google Scholar 

  • Robinson, H. 1985. The general form of the argument for Berkleian idealism. In Essays on Berkeley: A tercentennial Celebration, ed. J. Foster and H. Robinson. Oxford: Clarendon Press.

    Google Scholar 

  • Robinson, H. 1994. Perception. New York: Routledge.

    Google Scholar 

  • Russell, B. 1948. Human knowledge: Its scope and limits. London: Allen & Unwin.

    Google Scholar 

  • Sant’Anna, A., and K. Michaelian. 2019. Thinking about events: A pragmatic account of the objects of episodic hypothetical thought. Review of Philosophy and Psychology 10: 187–217.

    Google Scholar 

  • Smith, A.D. 2010. Disjunctivism and illusion. Philosophy and Phenomenological Research 80 (2): 384–410.

    Google Scholar 

  • Snowdon, P.F. 1981. Perception, vision, and causation. Proceedings of the Aristotelian Society 81: 175–192.

    Google Scholar 

  • Snowdon, P.F. 1990. The objects of perceptual experience. Proceedings of the Aristotelian Society Supplementary Volumes 64: 121–150.

    Google Scholar 

  • Snowdon, P.F. 2005. The formulation of disjunctivism: A response to fish. Proceedings of the Aristotelian Society 105: 129–141.

    Google Scholar 

  • Snowdon, P.F. 2008. ‘Hinton and the origins of disjunctivism’, in Haddock and Macpherson (eds.) Disjunctivism: Perception, Action, Knowledge. Oxford: Oxford University Press 35–56.

  • Sober, E. 1984. The nature of selection. Cambridge: Bradford Books/MIT Press.

    Google Scholar 

  • Soteriou, M., 2016, ‘The disjunctive theory of perception", The Stanford Encyclopedia of Philosophy, Edward N. Zalta (ed.) URL = <>.

  • Strawson P.F.,1979, ‘Perception and its objects’, in Macdonald G.F. (ed.) Perception and Identity, London: Palgrave.

  • Szpunar, K.K., J.M. Watson, and K.B. McDermott. 2007. Neural substrates of envisioning the future. Proceedings of the National Academy of Sciences of the United States of America 104 (2): 642–647.

    Google Scholar 

  • Tulving, E. 1985. Memory and consciousness. Canadian Psychology 26 (1): 1–12.

    Google Scholar 

  • Tulving, E., 2011, ‘Origin of autonoesis in episodic memory’. In H. L. Roediger et al (eds.) The nature of remembering: Essays in honor of Robert G. Crowder, Washington, DC: American Psychological Association, 17–34.

  • Tye, M. 1984. The adverbial theory of visual experience. Philosophical Review 93: 195–225.

    Google Scholar 

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I would like to thank people whose comments and criticism on this paper made me improve it considerably, especially two anonymous referees, Bill Wringe, Nick DiBella, Tufan Kıymaz audiences at Bilkent University and at Université Grenoble Alpes (where a few of these ideas were presented as part of another paper), and the editors of this special issue, Kourken Michaelian, André Sant’Anna, and Denis Perrin.

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Aranyosi, I. Mental Time Travel and Disjunctivism. Rev.Phil.Psych. 11, 367–384 (2020).

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