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Walter B., an affable, outgoing man of forty-nine, came to see me in 2006. As a teenager, following a head injury, he had developed epileptic seizures—these first took the form of attacks of déjà vu that might occur dozens of times a day. Sometimes he would hear music that no one else could hear. He had no idea what was happening to him and, fearing ridicule or worse, kept his strange experiences to himself.
On Monday, February 16, I could say I felt well, in my usual state of health—at least such health and energy as a fairly active eighty-one-year-old can hope to enjoy—and this despite learning, a month earlier, that much of my liver was occupied by metastatic cancer.
We all distinguish between plants and animals. We understand that plants, in general, are immobile, rooted in the ground; they spread their green leaves to the heavens and feed on sunlight and soil. We understand that animals, in contrast, are mobile, moving from place to place, foraging or hunting for food; they have easily recognized behaviors of various sorts. Plants and animals have evolved along two profoundly different paths (fungi have yet another), and they are wholly different in their forms and modes of life. And yet, Darwin insisted, they were closer than one might think.
There is, it seems, no mechanism in the mind or the brain for ensuring the truth, or at least the veridical character, of our recollections. We have no direct access to historical truth, and what we feel or assert to be true depends as much on our imagination as our senses. There is no way by which the events of the world can be directly transmitted or recorded in our brains; they are experienced and constructed in a highly subjective way, which is different in every individual to begin with, and differently reinterpreted or reexperienced whenever they are recollected.