This week the Brains Blog is hosting a symposium on Muhammad Ali Khalidi’s new book Cognitive Ontology: Taxonomic practices in the Mind-Brain Sciences (Cambridge University Press). Over the next four days, we will have four posts from Khalidi summarizing central arguments within the book as well as four commentary posts from Zoe Drayson (UC Davis), Joseph McCaffrey (University of Nebraska Omaha), Javier Gomez-Lavin (Purdue), and our own Zina Ward (Florida State).
-Trey Boone, Associate Editor
Many thanks to the Brains Blog, especially Dan Burnston and Trey Boone, for giving me space to try to summarize my book. I’m also very grateful to the commentators for their feedback. I look forward to reading what they have to say, as well as to any comments that other readers might have. For the sake of brevity, I’ve omitted citations from these posts, but they can all be found in the book.
How is one supposed to survey the entire domain of cognition and provide an ontological account of it? The approach I settled on in my book was to choose a number of representative categories from recent theorizing in cognitive science and see whether each could be considered a natural kind, and if so, what kind of kind it was. What are its main features? How is it individuated? How does it relate to other kinds? Does it have any subordinate or superordinate kinds? The thought was that this would give us a better idea of which cognitive categories are plausible candidates for corresponding to real kinds, as well as some idea of the nature of cognitive kinds in general. If these categories are somewhat representative and identify typical elements in the ontology of the cognitive sciences, then we might be able to emerge with certain conclusions about the metaphysical nature of the cognitive domain.
Some of the categories that I discuss in the book would likely make it onto anyone’s list of candidates for cognitive kinds: concepts, episodic memory, and cognitive biases and heuristics. Others might seem more like properties than kinds, innateness and domain specificity, but I argue that that distinction doesn’t run very deep. Yet others may be unfamiliar or outlandish. “Language-thought processes” is my label for whatever cognitive processes are responsible for Sapir-Whorf effects. Finally, body dysmorphic disorder is a psychiatric condition that seems to have roots in atypical cognitive and perceptual traits, and hence qualifies as a candidate for a cognitive kind, at least in my view. Each of these theoretical constructs gets a chapter of its own in which I try to assess its claim to be a real kind in the cognitive domain (two of these chapters are co-authored with my collaborators, Joshua Mugg and Amy MacKinnon).
As I see it, the book makes two main contributions. First, it looks at cognitive science through the lens of natural kinds (or as I prefer to say, real kinds). Though numerous philosophers of cognitive science and psychology have deployed kind-talk in their theorizing about the mind-brain, asking such questions as whether emotions are natural kinds, or concepts are natural kinds, or autism is a natural kind, the chief innovation here is to do so more systematically using a new theory of kinds. This account of kinds has strong affinities with others but I have built on previous work in general philosophy of science to articulate a “Simple Causal Theory” of natural kinds, which conceives of kinds as “nodes in causal networks.” This theory associates kinds with recurrent causal structures, some of which involve mechanisms, while others don’t; some of which are etiological or diachronic, while others are synchronic; some of which are structural, while others are functional. I would argue that this ecumenical and pluralist account of real kinds is also realist, since it locates kinds in the causal structure of the world.
The second contribution that the book tries to make consists of proposing a new type of externalism, call it “scientific externalism” (though I don’t use that term in the book – I use a clunkier one, “environmental-etiological contextualism”), which holds that cognitive kinds are often individuated by scientific research programs in terms of their causal histories or in relation to their synchronic environments, or both. This externalism pertains primarily to cognitive kinds proper, rather than all kinds posited in the sciences of the mind-brain. Sometimes “cognitive science” is used in an expansive sense to include a range of disciplines and sub-disciplines from cellular and systems neuroscience to cognitive and social psychology. But the scope of the cognitive in this context is narrower: it concerns the explanation of the behavior of creatures who have evolved to flexibly process information in order to manipulate their natural and social environments. I claim that this domain is best approached from what Marr called the “computational level” and that its kinds are typically individuated externalistically.
One lesson of this approach is that if cognitive kinds are individuated both etiologically and with reference to their wider environments, they will not always coincide with neural kinds, which tend to be individuated either intrinsically, or with reference to different etiological and relational factors. That should not be a surprising result; different sciences, even closely related ones, individuate their subject matters differently and in crosscutting ways. But it does undermine the search for neat correlations between cognitive and neural kinds, the much sought-after “neural correlates” or the “structure-to-function mapping” of cognitive neuroscience. Many of the cognitive kinds that I discuss in the book (e.g. concepts, innateness, domain specificity, episodic memory, myside bias) are individuated with reference to evolutionary history, ontogeny, or environmental context. These factors are not always relevant to taxonomic practices in the neurosciences, which as many philosophers of neuroscience have recently emphasized, are dominated by mechanistic entities and explanations. Just as we would expect from other biological sciences, there is a many-to-many relationship between cognitive and neural kinds.
In the next two blogposts, I will try to show how these different taxonomic practices play out in various research programs in the cognitive sciences engaged in understanding the nature of concepts and episodic memory, respectively.