A post by Sarah Robins

While I was in graduate school, a group of psychologists at WashU brought Ben Pridmore to campus. Pridmore had recently won the World Memory Championship and held the record in speed cards, an event where one memorizes the order of a shuffled deck of cards (Ben achieved this in 24.97 seconds; a decade later, the record now stands at 13.96 seconds). Pridmore met with some of us to talk about his memory training—and of course to show off his speed cards. He described building memory palaces as the act of creating “an Escher painting in my head.”

Mnemonics have fascinated me ever since.

Mnemonics are tools and strategies that aid remembering, an assortment of individually and collectively designed strategies for improving retention.  They pose a challenge, which I refer to as the mnemonic puzzle:

Mnemonics demonstrate that to remember X, it is easier to encode more information rather than less. This is, on its face, counterintuitive. Remembering is effortful. Shouldn’t remembering more information require more effort?

There’s a simple answer to this question, and a more difficult one. The simple answer is that, when it comes to cognitive effort, mnemonics are a way of working smarter, not harder. Structuring information in certain ways—incorporating imagery, putting it to song, embedding it in a familiar place, etc.—facilitates retention. The more difficult answer would be one that tells us why. Do these techniques share certain features that make them so successful, or is success modulated by variation in individuals, information to be remembered, context, and more? Frankly, we don’t know. Mnemonics have been largely neglected by scientists and philosophers who theorize about and study memory (although it’s important to acknowledge pioneering work on this topic from Boyle 2022, Peeters & Segundo-Ortin 2019, and Sutton 2000).

The neglect comes, I think, from the suspicion that mnemonics are gimmicky. Our central exposure to them is in pop psychology books and apps designed to “hack the mind”; they’re a get-rich-quick scheme for cognition. I want to resist that characterization and propose instead that mnemonics offer a valuable and unique window into the mind. Learning how they work can shed light on cognition in general and, more particularly, on the relationship between memory and imagination.

My first significant attempt at demonstrating the value of mnemonics is a chapter in Philosophical Perspectives on Memory & Imagination (Routledge, edited by Anja Berninger and Íngrid Vendrell Ferran). Here I focus on the Method of Loci, or MoL, “the oldest surviving formal mnemonic” (Worthen and Hunt, 2011: 55). The MoL is a technique used to remember a set of items, often in a particular order or configuration. Users create a memory palace—a familiar space, place, structure, or route that is used as a mental framework for storing the items to be remembered. Palaces are typically familiar places: one’s childhood home, daily commute to work, or the layout of a favorite museum or neighborhood. With a palace selected, one then designates a mental image to correspond to each to-be-remembered item. The image accompanying each item is then slotted into the palace at intervals along the designated route. Often, the imaged items are combined, made to interact, or woven into a narrative. As a result of this elaborate encoding, the act of retrieval is relatively straightforward: one calls to mind the memory palace, initiates a mental ‘walk’, and as one sees images along the route, the associated items are recalled.

The MoL is widely used and wildly successful. Versions of the technique were used extensively by Roman rhetoricians (Yates 1966), Aboriginal Australians (Kelly 2016), and Medieval monks (Carruthers 2008). Today the technique is used by students—especially in fields like nursing where extensive memorization is required (e.g., Reser et al. 2021)—and by those competing in Memory Championships. Its effects on retention are evident from its first use and, with time and practice, can result in world records like Pridmore’s.   

In the chapter, I defend a particular view of the MoL. I argue that it is a way of remembering via constructive imagination. My aim is, first, to capture the role a memory palace plays in the act of remembering. Standardly, imagery and other such features are assigned one of two roles: either they are endemic, necessary features of memory or they are incidental, and therefore dispensable. Robert Hopkins (2018) illustrates this well. He argues that mental imagery is essential to episodic memory, while acknowledging that mental imagery can be used in other forms of remembering, but only as a “mere accompaniment” (p. 46). By calling it a ‘way of remembering,’ I am attempting to carve out an ontological middle ground.

The MoL is not a particular form of type of memory. Moreover, the technique isn’t necessary for remembering anything in particular. One could memorize the first 50,000 digits of pi without it. But, when one does use a memory palace to memorize pi, the role it plays in the activity is not mere accompaniment. This is because MoL employs not only imagery but structure. The technique improves retention by providing a structure for otherwise unstructured information. Given the lack of answers to the difficult question raised above, it’s hard to elaborate further. Is space the most important feature, or is it the connection to movement, or egocentric representations? Is it the combination with imagery, the building of a narrative? Even without settling this question, we can see that the technique involves grafting the palace structure to the to-be-remembered information. As a result, the palace is not generally detachable from the memory once it is securely encoded. If the palace is forgotten, then the sequence of items is, too.

The MoL is a way of remembering that makes extensive use of mental imagery and imaginative activity. I appeal to Van Leeuwen’s (2013) distinction between three senses of imagination—constructive imagining, attitude imagining, and imagistic imagining—to capture the activity central to this technique. While the MoL involves imagining in all three senses, it is the activity of constructive imagining that is most definitive. Constructive imagining is the activity of building novel mental representations, making use of pre-existing mental imagery to build something new. This is what the MoL does—combining familiar places and images in novel and sometimes bizarre ways that promote memorability.

In summary, the Method of Loci is a way of remembering via constructive imagination. I like this way of characterizing the MoL, for two reasons. First, defending it as a way of remembering highlights the potency of this technique. Well-built mnemonics can be more than mere aides. This provides further motivation to take on the difficult question of precisely how this occurs. 

Second, characterizing the MoL as a way of remembering via constructive imagination has a familiar ring to it. Lots of philosophers these days are talking about the relationship between memory and imagination. Many of them are continuists: they think remembering is a form of imagination (e.g., Michaelian 2016). I don’t. Insofar as I understand the terms of the debate, I am a discontinuist (Robins 2020).

Regardless of where you land on this debate, thinking through the MoL can help to clarify the options on the table. Even if MoL and remembering both involve constructive imagination, they engage this form of imagination in different ways. The MoL is a cultivated technique for encoding, one whose use generally involves training and whose employment is intentional and deliberate. The constructive imagining that it involves is available in awareness. Not so for remembering. Moreover, the MoL is consciously controlled, due to the training and cultivation it involves. The person using this technique decides not only the palace and images to use, but how they will be combined. There is no comparable level of control involved in remembering.

If this characterization is right, it puts pressure on the continuist to further explain the constructive imaginative process at work in remembering, so as to distinguish it from mere imagistic imagining. By comparing and contrasting these roles for constructive imagination, we are thus able to further triangulate on the sense in which remembering is constructive and imaginative. Many philosophers of memory and memory scientists are eager to disassociate themselves from a preservative, storage model of memory. They agree about what memory is not. The alternative, positive account of what memory is has been more difficult to suss out.

The MoL offers a constraint from the opposite direction. This mnemonic technique is a way of remembering that is highly constructive and imaginative, more so than what happens in standard remembering. Remembering may not be mere reproduction, but it is also not a deliberate and elaborately constructed mnemonic device. It lies somewhere in between.

References

Boyle, A. (2022). The mnemonic functions of episodic memory. Philosophiocal Psychology, 35: 327-349.

Carruthers, M. 2008. The Book of Memory: A Study of Memory in Medieval Culture, 2nd Ed. Cambridge: Cambridge University Press.

Hopkins, R. 2018. Imagining the Past: On the nature of episodic memory. In Perceptual Imagination and Perceptual Memory, ed. F. Macpherson & F. Dorsch, 46-71. Oxford: Oxford University Press.

Kelly, L. 2016. Knowledge and Power in Prehistoric Societies. Cambridge: Cambridge University Press. 

Michaelian, K. 2016. Mental Time Travel. Cambridge, Mass.: MIT Press.

Peeters, A. and M. Sgeundo-Ortin. 2019. Misplacing memories? An Enactive Approach to the Virtual Memory Palace. Consciousness & Cognition 76, epub, doi: 10.1016/j.concog.2019.102834. 

Reser, D., Simmons, M., Johns, E., Ghaly, A., Quayle, M., Dordevic, A.L., Tare, M., McArdle, A., Willems, J., Yunkaporta, T. (2021). Australian Aboriginal techniques for memorization: translation into a medical and allied health educational setting. PLOS ONE, https://doi.org/10.1371/journal.pone.o251710  

Robins, S. K. (2020). Defending Discontinuism, Naturally. Review of Philosophy and Psychology, 11(2), 469–486.

Sutton, J. (2000). Body, mind, and order: local memory and the control of mental representations in medieval and renaissance sciences of self. In Guy Freeland & Antony Corones (Eds.), 1543 And All That: word and image in the proto-scientific revolution (pp. 117-150). Dordrecht: Kluwer.

Van Leeuwen, N. 2013. The Meanings of “Imagine”, Part 1: Constructive Imagining. Philosophy Compass 8: 220–30.

Worthen, J. B. and R.R. Hunt. 2011. Mnemonology: Mnemonics for the 21st century. New York: Taylor & Francis, Psychology Press.

Yates, F. 1966. The Art of Memory. Chicago: University of Chicago Press.