Theory Diagrams of Motley Kinds12 min read

Over at The Junkjard, Felipe De Brigard has a very nice summary of work from the Imagination and Modal Cognition lab on the phenomenon of episodic counterfactual thinking (eCFT). The post is well worth reading, so will not get into a lot of details here (it is based on a relatively longer piece forthcoming at Psychological Science). However, some aspects of the post dovetails with some recent discussions we have had here, especially on thinking about representing “motley” kinds (such as cultural kinds).

In essence, motley kinds are natural kinds that decompose into sub-kinds each endowed with distinct (but possibly overlapping) properties. In the case of cultural kinds, this is what I have referred to as compositional pluralism; namely, the claim that cultural kinds come in different flavors and that it is important to both distinguish between the different flavors but also come up with a way to represent what they have in common.

It is clear that one of the consequences of more fully incorporating neuroscience into the cognitive social science manifold has been the discovery that a lot of things that were treated as unitary (non-motley) kinds, have turned out to be motley. This happened pretty early on with memory, so that today it is completely uncontroversial to speak of memory as a motley kind composed of distinct types, such as declarative versus non-declarative memory .

The same (and this will be the subject of a future post) happened to concepts, which were traditionally treated as unitary kinds in philosophy and even the first wave of psychological research initiated by the pioneering work of Eleanor Rosch and Carolyn Mervis. However, as most forcefully argued by the philosopher Edouard Machery (2009) in Doing without Concepts, the weight of the evidence in cognitive psychology points to the conclusion that concepts are a motley kind, and come in at least three flavors: Prototypes, exemplars, and theories, each endowed with distinct (but possibly overlapping) properties and causal powers.

Some people are distraught when something they thought of as a unitary kind is shown to be a motley kind. This distress sometimes takes the form of accusations of “conceptual incoherence”—a common occurrence in the case of cultural kinds (e.g., Smith 2016)—or (e.g., in the case of Machery with regard to concepts) calls for elimination of the kind on account of its very motleyness.

Although I will not get into a detailed defense of this argument, my own position is that both of these reactions are unwarranted. The first one puts the cart before the horse, focusing on an epistemic problem (“conceptual incoherence”) as if it was an issue of having faulty beliefs about the world. But if a given kind is in fact motley (a feature of the world not our representations) then conceptual “incoherence” is actually more faithful to the structure of the world than ersatz or artificially imposed conceptual “coherence.”

The call to elimination on the other hand, as has already been noted by others (e.g., Taylor and Vickers 2017; Weiskopf 2008) is surely an overreaction. Especially given the fact that a whole lot of kinds that have been thought of as unitary (in both the natural and special sciences) are turning out to be, upon further reflection, motley. In that respect following the heuristic “eliminate a kind if it turns out to be motley” would result in the disposal of most of the core phenomena across a number of scientific disciplines. So perhaps the problem is not with the world, but with philosophical theories of natural kinds that impose unity by fiat.

Another consideration against elimination is simply that the discovery of motley kinds in other fields (such as the cognitive neuropsychology of memory) has actually resulted in an efflorescence of research and clarification of how basic processes work and how core phenomena are generated. In other words, we have better accounts of memory and how it works now that we recognize it as a motley kind. This recognition has not resulted in “conceptual incoherence,” confusion, or cacophony. Although Machery (2009) does mount a strong case favoring the conclusion that confusion and cacophony have ruled the study the study of concepts in psychology historically, this outcome is not fore-ordained nor can it directly be laid at the steps of the facts that concepts are a motley kind.

Additionally, as noted in De Brigard’s post and in a previous post, when it comes to memory we are now discovering, in a fractal-like sense, that some of the sub-kinds (such as episodic memory) that were thought of as unitary are themselves motley! Such, that as Rubin (2017) notes in a recent contribution, we may be looking at a multiplicity of different things that have varying levels of resemblance to what we typically mean by (traditional) episodic memory.

De Brigard’s work fits into this approach, noting that the notion of (mnemonic) mental simulation is most likely a motley kind, which includes traditionally considered episodic memory (mentally simulating personal events from the past that actually occurred), but also episodic future thinking (mentally simulating personal events in the future that could occur) and semantic counterfactual thinking (thinking about non-actual but possible events or states of affairs not connected to personal experience). De Brigard argues for the importance of episodical counterfactual thinking (eCFT), mentally simulating events in the past that could have occurred, as its distinct kind of memory/simulation phenomenon.

Theoretically, the payoff of this type of motley decomposition is that it allows to both distinguish but also theoretically unify some key phenomena (e.g., remembering and simulating) while recasting things that were previously thought of as oppositions or discrete categories (e.g., “semantic” versus “episodic”) as ends in a bipolar continuum. This expands the range of theory in that a dimensional representation can accommodate “quirky” types of memory phenomena (e.g., déjà vu) by placing them in a multidimensional property space that disaggregates properties (e.g., explicitness and self-reference) that would otherwise be run together (Rubin 2017).

De Brigard thus assimilates eCFT into memory’s motley crew by placing it in a multidimensional property space distinguish a “Future/Past” dimension from an “Episodic/Semantic” one, overlaid with a third “modal” continuum anchored at “impossible” on the one end (a giant squid falling from the sky on New York City) to the actual on the other end, with the mere possible in the middle. We can thus define eCFT as the type of memory phenomenon combining high levels of “pastness” and “episodicness” but located in the “possible” region of the modality dimension. This is represented using the following diagram:

Which bears some resemblance to Rubin’s dimensional diagram of memory phenomena:

The main difference is that Rubin is selecting on De Brigard’s “pastness” pole and decomposes the “episodic” dimension into a self-reference plus “eventness.” The details of the relationships between these two representations are not as important (since De Brigard is subsuming memory under the larger category of simulation phenomena) as the fact that both De Brigard and Rubin, after acknowledging the motley nature of the phenomena they are dealing with, have to also then come up with a way to represent such motleyness, and both resort to using what Gordon Brett has referred to in a previous post as “theory diagrams.”

Which (finally) brings me to my point. Insofar (as already noted) as, both cognitive scientists studying memory and social scientists studying culture come to terms with (and make peace with) the motley nature of the particular kinds they study (e.g., memory and culture) then these types of diagrammatic representations go from being a mere addendum to pivotal tools with which to engage in theorizing. The reason for this is that, as noted in a previous post, the choice of diagrammatic representation (e.g., hierarchical versus dimensional) encodes substantive (but implicit) theoretical assumption about how the different subkinds relate to one another and whether they are conceived as having disjoint or partially overlapping properties. Theory diagrams, as Brett noted, encode thinking.

In addition, as noted by the difference between Rubin and De Brigard’s theory diagram, different ways of representing dimensions may also lead different insights or accommodate finer grained distinction. Rubin’s more conventional way of representing dimensions (as orthogonal Cartesian axes) tops out at three dimensions (in terms of visual representation). De Brigard innovates by rendering the third dimension as a “penumbra” (Dustin Stoltz‘s preferred term) like continuum spread within the Cartesian plane. This type of representation is particularly useful to represent dimensions with very fine gradation. In particular, as noted in previous posts, a lot of cultural kinds do differ along the “distribution” dimension and such a property fits very well with a De Brigard style representation.

Following this lead, and transforming my initial Rubin-like three-dimensional diagram of cultural kinds into a De Brigard diagram for cultural kinds looks like this:

There are several advantages to this type of representation. First the property of distribution is represented with a visual image-schema that most closely correspond to its fine-grained continuous nature. Second, the insertion of the distribution dimension into the center of the diagram “frees up” a cultural dimension, so that we could think of a taxonomy of cultural kind that would combine this representation with the previous Rubin-like one by including a third dimension thus allowing us to “up the motley” if such a thing were to be required. Overall, thinking seriously about the motley nature of cultural and other kinds, underscores the importance of having illuminating ways of representing such diversity. The work of representation and taxonomic ordering itself then can serve as a way to theorize the kind in question in ways that may lead to novel insights.

References

Machery, Edouard. 2009. Doing without Concepts. Oxford University Press.

Rubin, David C. 2019. “Placing Autobiographical Memory in a General Memory Organization.” Pp. 6–27 in The organization and structure of autobiographical memory, edited by J. Mace. Oxford University Press.

Smith, Christian. 2016. “The Conceptual Incoherence of ‘Culture’ in American Sociology.” The American Sociologist 47(4):388–415.

Taylor, Henry and Peter Vickers. 2017. “Conceptual Fragmentation and the Rise of Eliminativism.” European Journal for Philosophy of Science 7(1):17–40.

Weiskopf, Daniel Aaron. 2008. “The Plurality of Concepts.” Synthese 169(1):145.