Plastic Reason: An Anthropology of Brain Science in Embryogenetic Terms by Tobias Rees (review)

Tobias Rees’s Plastic Reason is a significant ethnographic window into debates on the plasticity of the human brain. The book is based on ethnographic fieldwork conducted in the early 2000s in the neurobiology laboratory of Alain Prochiantz, today a well-established professor at the prestigious Collège de France in Paris. At the time of Rees’s fieldwork Prochiantz’s scientific status was somewhat contested. His Parisian lab held a position that was marginal and provocative: that new cellular tissues are continuously generated, not just in the developing brain, but in the adult human brain. Such a view shook the received dogma (often attributed to Ramón y Cajal) that the adult brain was “a fixed and immutable cellular structure” (p. xi). According to Rees, Prochiantz’s hypothesis of a “silent embryogenesis” that continued in the mature human brain was not only a radical departure from this notion of a fixed brain but also a major challenge to the generally held view that plasticity of the brain meant “synaptic plasticity,” the production of new synaptic connections. This is not, however, the view of plasticity that Prochiantz advanced and that fascinates Rees. Along with a few other scientists, Prochiantz claimed that an ongoing production of new neurons in the adult brain expanded the view of plasticity to invest the whole brain, not just synapses. This is an entirely new dimension for brain plasticity, Rees claims, the plasticity of an organ that “never stands still, that is defined by an irreducible openness” (p. 8). Not without a certain hubris, Rees claims that in this transition “at stake was a shift from neurochemistry to plasticity” (p. 8) that is plasticity tout court.

Rees’s book is well written and engaging to read, with insightful analyses of the Parisian social life and brilliant historical excursions (unfortunately, in some cases, left to footnotes). It suffers, however, from two non-minor shortcomings. The first very visible issue is that the author has a tendency to conflate his situated and therefore partial ethnographic experience with an overall narrative in which what is at stake is nothing less than “the scandalous advent of plasticity . . . a new way of thinking and knowing the brain (and the human)” (p. 8). As he writes, “It was as if my fieldwork and plasticity literally coevolved” (p. 10). This lack of critical perspective creates a sort of short-circuit between Rees’s local analysis and universal (if not metaphysical) claims about the opening up of “a whole new, previously unthought-of possibility for thinking about the brain, the human,” something that materialized “just at the time when I arrived in the laboratory of Alain Prochiantz” (p. 229). This sort of naïve fetishism of the fragment reminds of Hegel’s experience when, upon witnessing the entrance of Napoleon in Jena, he claimed that he saw, as the story goes, the “world spirit on horseback.” Rees’s desire to become “the anthropologist of the sweeping and multifaceted motion initiated by plasticity” (“the anthropologist” not just one of the several scholars working on this) has not helped him offer a more contextualized (and therefore contestable) version of the specific plasticity he found in a French lab in the early 2000s. This totalizing view explains many of the grandiose claims in the final ethical section. Here it is not just that Prochiantz-Napoleon is believed to have inaugurated an entirely new epoch in the history of plasticity; more importantly it is that, for Rees, this discovery becomes the platform upon which “a whole new figure of the neurological human emerged, at home in a novel ethical space, equipped with a whole different . . . ethical equipment for (neuronal) sense making” (p. 278).

In this and other statements, the second major shortcoming emerges: the irresistible tendency to think everything in the singular—“plasticity,” “the human,” “the brain,” “the advent of plasticity” (not to mention “the anthropologist”)—something especially problematic when...