Look ye, carpenter, I dare say thou callest thyself a right good workmanlike workman, eh? Well, then, will it speak thoroughly well for thy work, if, when I come to mount this leg thou makest, I shall nevertheless feel another leg in the same identical place with it; that is, carpenter, my old lost leg; the flesh and blood one, I mean. Canst thou not drive that old Adam away?

[The carpenter replies:] Truly, sir, I begin to understand somewhat now. Yes, I have heard something curious on that score, sir; how that a dismasted man never entirely loses the feeling of his old spar, but it will be still p.r.i.c.king him at times. May I humbly ask if it be really so, sir?

It is, man [says Ahab]. Look, put thy live leg here in place where mine once was; so, now, here is only one distinct leg to the eye, yet two to the soul. Where thou feelest tingling life; there, exactly there, there to a hair, do I.

2. The importance of first-person accounts was emphasized by William James in his 1887 paper "The Consciousness of Lost Limbs":

In a delicate inquiry like this, little is to be gained by distributing circulars. A single patient with the right sort of lesion and a scientific mind, carefully cross-examined, is more likely to deepen our knowledge than a thousand circulars answered as the average patient answers them, even though the answers be never so thoroughly collated by the investigator.

3. The reason for this was not to be clarified until a century later, when it became possible to visualize, with fMRI, the gross changes in the brain's body mapping that could occur after an amputation. Michael Merzenich and his colleagues at UCSF, working with both monkeys and humans, have shown how rapid and radical such changes may be.

4. Despite categorical a.s.sertions by many that "congenital" phantoms cannot occur, there have been several reports (as Scatena has noted in a review of the subject) indicating that some people with aplasia-congenitally defective or absent limbs-do have phantoms. Klaus Poeck, in 1964, described an eleven-year-old girl born without forearms or hands who was able to "move" her phantom hands. As Poeck wrote, "In her first years at school, she had learned to solve simple arithmetic problems by counting with her fingers.... On these occasions she would place her phantom hands on the table and count the outstretched fingers one by one."

It is not clear why some people born without limbs have phantoms and some do not. What is clear, as Funk, Shiffrar, and Brugger observed in one study, is that those who do have phantoms seem to have cerebral "action observation systems" similar to those of normally limbed people, allowing them to grasp action patterns by observing others and to internalize these as mobile phantoms. Those born without limbs who do not have phantoms, Funk et al. propose, may have problems in motion perception, especially judging the movements of other people's limbs.

5. When Henry Head introduced the term "body image" (fifty or so years after Weir Mitch.e.l.l had introduced the term "phantom limb"), he did not mean it to refer to a purely sensory image or map in the brain-he had in mind an image or model of agency and action, and it is this which needs to be embodied in an artificial limb.

Philosophers like to speak of "embodiment" and "embodied agency," and there is no simpler place to study this than in the nature of phantoms and their embodiment in artificial limbs-prosthesis and phantom go together like body and soul. I have wondered whether some of Ludwig Wittgenstein's philosophical notions were suggested by his brother's phantom arm-thus his final work, On Certainty, starts from the certainty of the body, the body as embodied agency.

6. Wade Davis describes this in his book Into the Silence: The Great War, Mallory, and the Conquest of Everest.

7. Nonetheless, Nelson regarded his phantom as "a direct proof for the existence of the soul." The survival of a spiritual arm after a corporeal one was annihilated, he thought, epitomized the survival of the soul after bodily death.

For Captain Ahab, however, this was a matter for horror as much as wonder: "And if I still feel the smart of my crushed leg, though it be now so long dissolved; then, why mayst not thou, carpenter, feel the fiery pains of h.e.l.l forever, and without a body? Hah!"

8. This story, "The Man Who Fell Out of Bed," is related more fully in The Man Who Mistook His Wife for a Hat.

9. Several people have written to me with similar stories of sensing a presence just as they are going to sleep or waking. Linda P. observed that once, as she was drifting off to sleep, she felt "as if I was being held on my right side, as if someone had put their arms around me and was stroking my hair. It was a lovely feeling; then I remembered that I was alone, and [the feeling disappeared]."

Acknowledgments

I am most grateful, first and foremost, to the hundreds of patients and correspondents who have shared their experiences of hallucinations with me over many decades, and especially to those who have allowed me to quote their words and tell their stories in this book.

I owe an enormous debt to my friend and colleague Orrin Devinsky, who has stimulated my thoughts with his many published and forthcoming papers and referred many of his patients to me. I have enjoyed and benefited from discussions with Jan Dirk Blom and from reading his wonderfully comprehensive Dictionary of Hallucinations and Hallucinations: Research and Practice. I am deeply grateful for the friendship and advice of my colleagues Sue Barry, Bill Borden, William Burke, Kevin Cahill, Jonathan Cole, Douwe Draaisma, Henrik Ehrsson, Dominic ffytche, Steven Frucht, Mark Green, James Lance, Richard Mayeux, Alvaro Pascual-Leone, Stanley Prusiner, V. S. Ramachandran, and Leonard Shengold. And I am grateful to Gale Delaney, Andreas Mavromatis, Lylas Mogk, Jeff Odel, and Robert Teunisse for sharing their own experiences (and sometimes patients) with me.

I must also thank Molly Birnbaum, Daniel Breslaw, Leslie Burkhardt, Elizabeth Chase, Allen Furbeck, Kai Furbeck, Ben Helfgott, Richard Howard, Hazel Rossotti, Peter Selgin, Amy Tan, Bonnie Thompson, Kappa Waugh, and Edward Weinberger. Eveline Honig, Audrey Kindred, Sharon Smith, and others at the Narcolepsy Network kindly introduced me to many people with narcolepsy and sleep paralysis. Bill Hayes, a friend and a writer whom I much admire, read each chapter with his own writerly eye and made many valuable suggestions.

For their support and encouragement, I thank David and Susie Sainsbury; Dan Frank, who has patiently reviewed draft after draft of this book (as with many previous ones); Hailey Wojcik, invaluable research a.s.sistant, typist, and swimming companion; and Kate Edgar, my friend, editor, and collaborator for thirty years, to whom this book is dedicated.

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