Andrés Vaccari

The Brain Takes Shape: An Early History
By Robert L. Martensen (Oxford University Press, 2004)

(Published in Metascience 15:3, December 2006)

Few people nowadays would dispute that the brain is the seat of personhood, the locus of all cognitive, sensory and emotional processes. This commonsensical, distinctively Western idea has had a relatively short but convoluted history, beginning in early modern Europe. Even before modern neurobiology began to unlock the secrets of the brain, the notion that the ‘seat of the soul’ was in the head already enjoyed widespread cultural currency. A critical turning point was the dualistic metaphysics of René Descartes (1596-1650), which asserted that the pineal gland at the centre of the brain (he called it ‘gland H’) was the point of contact between the immaterial soul and the mortal body. Descartes devoted the bulk of his Treatise on Man (published posthumously in Latin in 1662, and in French in 1664) to an examination of the brain, dreaming up a fanciful machine that duplicated all of its functions.

In this book Robert Martensen sets out to examine how the brain came to be enthroned as the headquarters of the self. For ancient Greek and renaissance medicine the notion that the soul had a privileged place of residence in the body would have made little sense, as there were various kinds of souls inhabiting bodies, and no sharp distinction between the spiritual and material. Nonetheless, the most influential traditions postulated a hierarchy of organs; for example, Aristotle (following ancient traditions) believed the most important organ was the heart, and Galen established a complex chain of command between brain, heart and liver (paying more attention to the ventricles and meninges than the brain itself). But there also was a strong tradition that linked the brain with intelligence and emotion (Hippocrates and Plato, for example).

The main subject of Martensen’s study is the Oxford physician Thomas Willis (1621-1675), who published the first wide-ranging and carefully illustrated treatise on the anatomy of the brain (Cerebri Anatome, 1664). Gathering around Willis we encounter a number of precursors and successors (Vesalius, Paraceulsus, Harvey, Descartes, Locke, etc.), and key traditions and developments converging in his detailed and methodical dissections. Martensen sets the stage with the notions of ‘presence’ and ‘likeness’ (borrowed from the work of German art historian Hans Belting). Belting argued that the early modern period was characterized by a shift from the former to the latter, that is, from “the tendency to imagine knowledge of the world and the world itself as dependent on the spiritual capacity and interaction of knower and known” to “the epistemic assumption that one may know substantial aspects of material nature and depict them accurately without relying heavily on spiritual capacities” (3).

Martensen notes an interesting paradox: the rise of visuality in modern science is contemporaneous with the iconoclastic drive of the Reformation to downplay the role of visual demonstrations. He takes this as a sign of “a gradual but inexorable move on the part of early modern learned Europeans to consider the Book of Nature and the Bible, or Book of God, … as two separate domains” (10). However, although the theme of likeness/presence returns throughout the book, it is not Martensen’s main concern, and it is left largely unexplored both in terms of its analytic potential and the significant problems it faces. Most importantly, the notion of ‘likeness’ tends to flatten a variety of representational strategies and philosophies into a single visual regime, as well as assuming a natural relationship between image and object or experience.

In fact, The Brain Takes Shape often reads like a series of stand-alone essays strung together without a coherent unifying theme. The main disadvantage with such an approach is that fruitful lines of enquiry are not given the scrutiny they deserve, and the reader can easily get lost in the branches. On the positive side, this study effectively conveys a sense of the complex and heterogeneous dimensions that intersected in early modern brain anatomy, a map of the forces mobilized and worlds traversed by this baffling piece of grey matter on the dissector’s table.
Martensen examines earlier Neo-Platonic, vitalist and alchemical models, arguing for their large influence in Willis’ medical practice and his conception of the body. He emphasizes in particular the torrid political and religious climate in England at the time: the English Civil War, the abolition of the monarchy, the execution of Charles I, Cromwell’s protectorate, and, eventually, the restoration of order. Martensen masterfully plots how anxieties relating to power, authority and sovereignty were reflected in Willis’ musings about the brain and its place in the bodily hierarchy. One of Willis’ accomplishments was “to make the interior of the human body express in its own terms the interests and cosmological assumptions of the external group that supported it without ever having to acknowledge their artifice” (206).

Also amongst the topics covered, Martensen addresses the social aspects of early modern knowledge (patronage, the witnessing of evidence, etc.), the history of human dissection in its socio-political context, the implications of a ‘neurocentric body’ for ideas of gender and the treatment of specifically female disorders, the emergence of an empirico-rational diagnostics and therapeutics, and lastly the fate of the ‘cerebral body’ in modern and postmodern times. The last chapter also contains a valuable discussion on methodological aspects of an anthropological approach to the history of knowledge.

What I found of particular interest is Martensen’s argument that Willis’ close observation of the brain’s structure supported a shift from the pneumatico-hydraulic system of Greek medicine (which Descartes re-elaborated in terms of baroque technology) to one that underlined solid tissues. The models springing from Galenic medicine and other sources relied heavily on the paradigm of cavities and fluids, thus directing the course of observation and anatomy towards the investigation of ventricles, arteries and other organs suitable for the conveyance and transformation of fluids. The seemingly solid nerves, on the other hand, seemed to perform their work by rather more mysterious means. The notion of a ‘nervous juice’ is an intriguing transitional notion developing out of the ‘animal spirits’, but specific to the phenomenon of nerve transmission. One of the remarkable achievements of Willis was to ground brain science (with an emphasis on the solid bits) on a strong empirical basis, without necessarily offering an accompanying ontology (the opposite, in certain ways, of what Descartes did). In terms of his metaphysics of the body, Martensen shows that Willis was a man of his time. Another fascinating chapter in this history is the emergence of British empiricism, in particular with John Locke (1632-1704), perhaps Willis’ most famous student. Frustrated at the lack of ‘scientifical’ knowledge about bodies, Locke opted for a ‘mind without brain’ (as Martensen calls it): a philosophy of ideas independent of physiology.

Martensen’s training as a physician makes him sensitive to details, and to historical ruptures and continuities that may remain obscure to other historians of science. His meticulous research draws out a wealth of micro-historical observation. With a doctor’s eye for his subject, Martensen is keenly perceptive of the concrete material culture that supports, surrounds and shapes the everyday work of physicians and medical practitioners. The Brain Takes Shape is a substantial contribution to the historiography of early modern diagnostics and therapeutics. Naturally, it would be impossible to cover everything, or to subsume accuracy and attention to the facts for the sake of a good story. But I regretted that this rigorous approach was not framed in a more engaging, fluent narrative, and that a better balance between the micro and macro picture was wanting.