Soul Made Flesh: The Discovery of the Brain--And How It Changed the World

The American writer Carl Zimmer has written a brilliant book on Thomas Willis (1621-75), the founder of neurology. Willis discovered the human brain's role and importance, and was the first to examine how it worked. Willis was part of the remarkable generation of Britons who founded the Royal Society, aiming to understand the physical world: William Harvey, who by discovering the circulation of the blood had, as Willis said, created `a new foundation of medicine', Christopher Wren, Robert Hooke, Robert Boyle and William Petty, whom Karl Marx called the father of political economy. To keep the Restoration Stuart state on side, they excluded from the Society the materialist Thomas Hobbes, who had said that the mind was `matter in motion'. As the Platonist Henry More realised, `No spirit, no God'. Willis' book `The Anatomy of the Brain and Nerves' mapped the brain, and was the first unified treatment of the brain and the nerves. The new science combined anatomical study of the human brain with comparisons to animal brains, experiments and medical observations. He identified the loop of arteries that supplies the brain, which became known as the Circle of Willis. The 20th century neurologist Lord Brain described Willis as `the Harvey of the nervous system'. Willis "created a material explanation of the soul and its disorders. ... He had transformed the traditional three-part soul, which had existed since Plato, into the corpuscular chemistry of the nervous system. The soul was not just moved to the brain but limited to it, and only through the nerves could it experience the world." But the idealist philosopher John Locke attacked Willis' materialist approach, holding back neurology's development. Zimmer explains, "Locke also influenced the way philosophers pondered the mind itself. He dismissed details of neurology and concerned himself with ideas and how they fit together, and generations of philosophers followed his lead. It would take neurologists 150 years to show that Willis was right, that studying the anatomy and chemistry of the brain can indeed reveal the workings of the mind, that they can map the geography of passion, reason, and memory."

Debates about the "soul" have raged for millennia. Because we tend to think these debates are confined to the realms of philosophy and theology, we ignore the contribution medicine has made to our perception of the "self". Carl Zimmer's examination of the debate and its significant participants enlarges our outlook. His depiction of the life of Thomas Willis in tumultuous 17th Century Britain reveals the pioneering research that lead to a new view of the body's functions. The "soul", so long a mysterious concept, began to be exposed in the brain and its relation to the rest of the body. The study of illnesses, particularly those associated with behaviour, disclosed how false traditional views truly were. The ancients, Zimmer explains, had varying ideas about the body's workings. He summarises the many views, noting how certain ancient thinkers, particularly Galen, came to be adopted by Christianity. Once admitted within the Church's fold, their teachings became part of the established dogma. Orthodoxy substituted for observation, inhibiting learning. The number of lives lost is incalcuable, but dissent through evidence was perilous. Even the Greeks, Zimmer reminds us, considered dismembering cadavers distasteful. Real medicine was thus kept in check for centuries. While Protestantism overthrew many dogmas, medicine remained a restrained science. The issue of the "soul", where it resided and how it functioned, remained an enigma. The stomach, liver and heart were all candidates for the home of the "soul". The brain was viewed as a "useless mass of grey porridge". Zimmer's illuminating study depicts the revolution Willis wrought in explaining the brain's central role. He learned to dissect the brain, which decays faster than other organs, and initiated explanations of the nervous system. His illustrator was none other than Christopher Wren, famous Restoration architect. Together, they demonstrated the brain's arterial and nerve arrangement in what became known as the Circle of Willis - the entwined network of signal systems and energy resources. The collaboration was published as "The Anatomy of the Brain", the founding document of the science of neurology.Willis established what Zimmer describes as the "four pillars of neurology". The first of these is the interaction of the body through the nerves to the brain. Second, the body's activities can be mapped in particular areas in the brain. Stimulation and response thus become predictable - showing the brain is structured, not merely an incohate melange of "grey porridge". Third, Willis and his followers demonstrated the similar structure of the brains of all animals. Tests showed clearly the body-brain interaction is common to all creatures. Finally, abnormal behaviour and many illnesses can be chemically treated. Although Zimmer describes today's world as "awash in brain drugs", benefits can be derived through proper therapy.Although Zimmer covers a wealth of material,

Soul Made Flesh is a masterful blend of science, history and philosophy. Carl Zimmer weaves a fascinating narrative around an overlooked historical moment - the discovery of the brain - by looping back and forth through the centuries from ancient Greece to the new millennium while keeping his gaze fixed on 17th century England. As someone schooled in the classics, whose college curriculum consisted wholly of the Great Books, I found Zimmer's new book particularly satisfying to read. Soul Made Flesh is far more than a gallop through history. It goes well beyond identifying who was influenced by who, what I call the "connecting the dots through time" approach often conveyed in reverential tones by writers who have read only secondary sources of Aristotle, Descartes or Locke. Zimmer's book breathes life into the classics by allowing the reader to "overhear" Willis and his Oxford Circle peers examining, questioning and arguing about these texts even as they toil to expand anatomical knowledge beyond all previous bounds.As I neared the end of Soul Made Flesh, I happened to read a Boston Globe Magazine interview with Andrea Barrett, author of The Voyage of the Narwhal and, like Zimmer, a gifted science essayist. I was struck by a passage in which Barrett talks about "the unspoken disappointment of science" - research stolen or lost, specimens left in sunken ships, a life's worth of work made irrelevant by changing times. "I think about [loss] a lot. It's a very, very real part of science, but it's not the part that gets passed down," says Barrett. "We know the stories of famous scientists, but we don't hear the stories of people working hard and passionately half a tier down." Barrett could have been talking about Zimmer's book as much as her own. In Soul Made Flesh, a disillusioned old man hands over his research notes to a young passerby, scientific manuscripts are reworked to appease punitive church leaders, careers in medicine are interrupted by war, and cadavers eventually rot. Most everyone who reads Soul Made Flesh will feel a deep appreciation to Zimmer for persevering in his own research and writing to deliver a book that ensures Willis' founding contributions to neuroscience will be known, discussed and remembered.

Carl Zimmer is one of the finest science writers of our generation. This is an amazing peek into the origins of modern science. It helps us see the shape of the lens through which we view reality today. It's also an astonishing story.

Soul Made Flesh is a marvelously nuanced and accessible work about a little-known moment in the history of science--the birth of modern neurology. Central to this revolutionary period is the Englishman Thomas Willis (1621-1675), a man of humble beginnings who rises by his own wits to become the most famous physician and scientist of his time. During his life, Willis describes the brain and nervous system in an entirely new way and quite literally changes the way scientists approach disease, treatment, and research into the human body. It's an amazing accomplishment for someone so obscure to most modern readers. Zimmer has, perhaps, changed that for good, because he offers a wonderfully thoughtful examination of Willis the man, scientist, and physician that nearly anyone will find a pleasure to read.Zimmer includes in early chapters a splendid primer on the state of medical/philosophical thought during Willis's formative years of education in Oxford. This gallop through history is often botched in science books, but Zimmer eases you along in an informed and even entertaining way from Hippocrates, Aristotle, Galen, Aquinas, Copernicus, Galileo, and Descartes up to Willis's contemporaries, such as Harvey. Zimmer knows his stuff and gets it all just right. Occasionally I wished he had written a bit more about a few of the more colorful figures, like the truly bizarre Descartes, but it's no flaw of the book. Zimmer hits a stride when Willis and his circle at Oxford begin their regular meetings and examinations together. It's an exciting tale to tell and one feels drawn right into the era with wonderful descriptions of the sights and not so pleasant smells of 17th century England. He also profiles many of the famous and sometimes obscure characters of the period.Amidst all the scientific chronicles of dissection, hangings, brain injuries, seizures, cholera, and other mostly horrible matters of the flesh, there are the constant metaphysical questions that arise about the soul. It is this balance of the physic and metaphysic that makes this book so satisfying. But I think the book's real triumph is the celebration of Willis's fine mind and accomplishment through so much adversity.