The Problem of Animal Consciousness
Do Horses Gallop in Their Sleep?
By Matt Cartmill Let me propose a thought experiment. Imagine, if you will, that there's a certain clump of nerve cells in the brain that's essential for conscious awareness. Now suppose that a certain drug suppresses neural activity in just this nucleus, with no effect on the rest of the brain. Subjects who take this drug do things as usual, but they experience nothing. The drug converts them into sleepwalkers. Finally, imagine that I've developed a new form of this drug, which has permanent effects. It abolishes consciousness forever, with no effect on behavior. I want to test it on you. How much will you charge to take it? I think the question answers itself. Spending your life as a sleepwalker is equivalent to being dead, and so you will charge me whatever price you would charge to commit suicide. I offer this thought experiment to dispel the notion that conscious awareness is too metaphysical and subjective a phenomenon for science to concern itself with. The phenomenon of consciousness is the source of all value in our lives. As such, it should be at the top of the scientiﬁc agenda. Yet despite its fundamental importance, consciousness is a subject that most scientists are reluctant to deal with. We know practically nothing about either its mechanisms or its evolution. In fact, many distinguished scientists and philosophers believe that consciousness has no evolutionary history, because they think that human beings are the only creatures that have it. Although most scientists will admit in private that our close animal relatives probably have mental lives something like ours (because, after all, they have bodies and brains and behavior that resemble ours), a lot of scientists are reluctant to say so plainly and publicly; and those who do can count on being accused of sentimentality and anthropomorphism. If you have a dog, you have probably had the experience of seeing your dog search out a favorite toy and bring it to you in hopes of getting you to play with him. It's hard even to describe these familiar experiences without saying things like, "The dog was trying to ﬁnd his ball," or "The dog wanted me to play with him." But scientists aren't supposed to say things like that, at least when we have our lab coats on. If we discuss such things at all, we prefer to do so in some way that doesn't involve attributing intentions or any other mental states to the dog. There are at least two ways we can do this. First, we can use clumsy behavioral circumlocutions for mental language. Instead of saying, "The dog looked for his ball until he found it," we can say something like, "The dog exhibited repeated bouts of investigative behavior, which ceased after he contacted the ball." This somehow manages to suggest that the dog wasn't thinking about the ball while he was looking for it, and that he didn't perceive anything when he got it in his mouth. Second, if we ﬁnd these circumlocutions silly and tedious, we can adopt some variant of what is sometimes called "logical behaviorism," in which the mental words are still used but they are redeﬁned in terms of the probabilities of certain behaviors. In this view, a dog's intentions and desires and beliefs turn out, when properly understood, not to be something inside the dog, but theoretical constructs pinned on the dog by a human observer. Therefore, the human observer can know whether the dog has intentions and desires and beliefs, but the dog can't.
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The Problem of Animal Consciousness
Why Not Attribute Consciousness to Animals? Why do scientists and philosophers go through all these contortions to avoid attributing mental states to animals? There are several reasons, some of which are better than others....