The Ravenous Brain: How the New Science of Consciousness Explains Our Insatiable Search for Meaning Read Online Free Page A

wiring into his brain.
    Descartes recognized, though, that no matter how malicious this demon was, there was one realm of thought that was certain, impervious to the demon’s illusions: his own existence as a thinking being. Like Neo, you may believe in blissful ignorance that you have the same body you’ve always had, as that is what the computers feed into your senses. But the one act beyond the power of these evil computers is to fool you about your own existence. There are two options: If you do believe you exist, then logically you must exist—at least as some kind of conscious being—since the act of believing requires the existence of a conscious being to believe it. Alternatively, if you try, somehow, to believe you don’t exist, then the very act of doubting confirms your existence again, since doubt also requires a conscious being to perform the doubting, as it were. Therefore, just by the act of thinking (with doubt as one example), you know that there must be a conscious entity around, and you also know that it is you!
    In the meditations, Descartes articulated this idea as: “I must finally conclude that this proposition, I am, I exist, is necessarily true whenever it is put forward by me or conceived in my mind.” But he put it more famously and succinctly in Discourse on the Method as “ Cogito ergo sum ” (I think therefore I am).
    One of Descartes’ main arguments for justifying the mind-body duality was intimately bound to these views on doubt. The argument was deceptively simple and superficially persuasive: Because we can so effectively doubt the existence of our own bodies, but can never doubt the existence of our own minds, the mind is completely distinct from and independent of the body (a modern spin on this argument might substitute “body” for “brain”).
    The brilliant philosopher, mathematician, and logician Gottfried Wilhelm von Leibniz, who was born around the time of Descartes’ death, was quick to vilify Descartes. Leibniz pointed out that all Descartes had actually shown was that he could contemplate that his conscious mind was distinct from his body. He certainly hadn’t proven anything. This critique can be illustrated by a slight twist on a well-known example. Say I happen to be walking the streets of Metropolis and from a distance I see a tall, well-built man with thick, ugly glasses hurrying into a telephone cubicle in an alley. My friend tells me that he’s the Daily Planet reporter, Clark Kent. Suddenly, on the other side of the street, five gunmen descend on a security van, looking to steal hundreds of thousands of dollars in cash. I’m terrified and excited at the same time, and believe they’ll get away with it. Then I feel a momentary swirling wind, and miraculously, as if from nowhere, Superman flies past me toward the criminals. He has them disarmed and tied up in ropes in the blink of an eye. My friend looks at me, his head cocked sideways, and asks: “Do you . . . do you think there’s any chance that this Clark Kent guy is the same person as Superman?” I laugh at how ludicrous that suggestion is, and quickly retort: “Listen, I definitely know who Superman is—I’ve seen him fly around loads of times. I’ve even interviewed him twice for my magazine. I barely know this Clark Kent guy, and besides, from my fuzzy glimpse of him a minute ago, he even looks different because he wears glasses. Therefore I’m certain that Superman and Clark Kent are two completely distinct people.” My friend nods, impressed at my watertight logic, and I feel a warm, comforting sense of smugness at yet another example of my superior intellect.
    The Superman observer is making two mistakes here: First, he’s assuming that his own level of knowledge of Superman/Clark Kent is an actual characteristic of Superman/Clark Kent ; second, he’s assuming that superficial differences between Superman and Clark Kent must mean they are different people rather than two versions of