The mind is the only scientific subject left in which a writer can muse in a belletristic way and not be warned off under the Act against Dabbling in Matters about which only the White Coats are Empowered to Talk. Civilisation would grind to a halt if we forgot the science of solid-state physics (computers) or elasticity (bridges and buildings) or gas dynamics (jet engines), but we can go on quite happily in a fog of ignorance about our minds.
Stephen Wilson's book cannot dispel the fog, but he has assembled a fine selection from great names of psychology, philosophy and neuroscience (Plato, Freud, William James, etc) and from literature, including Shakespeare, Proust and Woolf. Not all the passages have worn equally well - Jung, Adler and Klein are probably past their sell-by - and the blurb refers to "the latest discoveries of neuroscience", which are thin on the ground here.
This is understandable. Hardcore neuroscience doesn't read nearly as well as Oliver Sacks. The truth is that, despite the Nineties having been the "Decade of the Brain" in America, with an avalanche of research dollars, the harvest has so far been meagre.
All the big questions remain more or less open. What is consciousness? Are mind and matter distinct, or two sides of the same coin, or what? How are memory traces established in the brain (it is emphatically not like a computer memory with everything in its precisely located box)?
Wilson dedicates the book to his mentor Anthony Storr, a great humanistic psychiatrist. Although hardline behaviourists such as Watson and Skinner have their say, the flavour of the book is given by such cultured, rounded figures as Storr and Sacks. Wilson gives us a guided tour with the extracts set off by his running commentary and biographical notes. This format makes it both a good primer and an agreeable recapitulator for old hands.
As ever, Oliver Sacks stands out because he writes vividly about real people with conditions that can teach us something about the mind. Our visual picture of the world, apparently so seamless, is the result of perhaps 50 coordinated visual systems. Sacks recounts the case of someone who had lost the system that processes movement of images: vision was there but the flow of water from a tap was arrested in jerky stills. Ever since the classic 1959 paper "What the Frog's Eye tells the Frog's Brain" (Lettvin et al, not included here), we have known that individual neurons in the visual system respond to specific things. What we are still no nearer is an understanding of how these myriad, mechanical subsystems produce that gorgeously rich picture, at far better than the best computer resolution.
The book's choicest pleasures come near the end, under the heading of Consciousness. Sex is crucial for the problem of how the mind affects the body, being under semi-conscious control but subject at times to the distressing condition: spirit willing but flesh weak. The 18th-century surgeon John Hunter sounds startlingly modern in his exposition of this conundrum.
In writing about the mind, the journey not the arrival matters. If there is a double helix of the brain, we have yet to find it. Meanwhile, there is much pleasure to be had by nibbling away at our ignorance, as this book does so appetisingly.