Friday, July 07, 2006

Spiritual Machines or Abolition of Man?

By the year 2045, we will have created robotic intelligence that will be one billion times more powerful than the biological intelligence of human beings. At that point, we will transcend our biology by uploading our human consciousness into "spiritual machines." That's the prediction of Ray Kurzweil in his book The Singularity is Near: When Humans Transcend Biology. He welcomes this prospect, because he foresees that by uploading his consciousness into a robot, he will become immortal, and his intelligence will be increased.

But many people fear this. Religious conservatives see this as what C.S. Lewis called "the abolition of man." The modern quest to conquer nature might lead us to conquer human nature, perhaps by using our technological power to transform our nature so that we might be immortal. But in doing that, we would actually annihilate ourselves.

This leads religious conservatives like Carson Holloway to warn that Darwinian conservatism provides no obstacle to such uses of technology to alter and eventually abolish human nature. After all, if our existing human nature is understood as a product of biological evolution that serves no cosmic purpose, then why shouldn't we use our power to bring about a technological evolution of our nature to improve it in ways that we might hope would make us happier and more secure?

But if one believes in a cosmic teleological order designed by God, as Holloway does, then it's hard to see why he worries about the abolition of human nature by technology. Such a worry suggests that God's teleological order is so fragile that it can be upset by human technology. That's why Peter Lawler suggests that to speak about the technological abolition of human nature is an exaggeration.

Like Lawler, I have argued (in the last chapter of Darwinian Conservatism and in my March 8th posting on transhumanism)that human nature will endure, and that both the fearful opponents of transhumanism and the hopeful proponents exaggerate the power of technology for changing human nature.

But what should be said about Kurzweil? He rejects the idea of "transhumanism," because he thinks that what makes us human--the software patterns of information that make us the people that we are--will be preserved in nonbiological hardware.

Kurzweil is famous as a successful inventor who has developed optical scanners and voice recognition software. He identifies himself as a "pattern recognition scientist." Rather than being a "materialist," Kurzweil insists that he is a "patternist" who believes that emergent patterns of information are more important than the materials that embody them. That's why he thinks the human patterns of conscious experience can be preserved even in the complex computational mechanisms of the future.

Kurzweil's main idea is "that there is a specific game plan for achieving human-level intelligence in a machine: reverse engineer the parallel, chaotic, self-organizing, and fractal methods used in the human brain and apply these methods to modern computational software" (Singularity, 439).

Since I have argued that the human mind arose by emergent evolution in the brain, I would have to agree that at least in principle it should be possible to duplicate human intelligence in machines that replicate the causal complexity of the brain. But while I concede this as true in principle, I am skeptical that it will ever be possible in practice, because I doubt that we will ever have the perfect understanding of the brain that will allow us to "reverse engineer" its activity and then replicate it in a machine.

Some religious conservatives would disagree. They would say that the human mind cannot even in principle be replicated in a machine, because the machine would lack the immaterial spirituality that constitutes the human soul as created by God.

But even if God has created the human soul, isn't it clear that He has chosen to exercise His creation through the natural causal powers of the human brain and nervous system? The human mind arises in a human individual when the brain has developed to a critical point of complexity while interacting with the social and physical world in the early development of the individual.

But if this is so, then in principle we could replicate human intelligence if we knew enough about the causal powers of the brain to replicate them artificially in a machine. And yet I think this is unlikely, simply because I cannot foresee that our understanding of those causal powers will ever be deep enough to make this possible in practice. Kurzweil says that "the principles of the design of the brain are simpler than they appear" (446). To me, this seems remarkably naive.

Nevertheless, some of Kurzweil's critics would say that I have conceded too much to him. For example, John Searle insists that no computer could ever replicate human intelligence. He uses his famous Chinese Room Argument to support this claim.

In Are We Spiritual Machines?, a book edited by Jay Richards and published by Discovery Institute Press, Kurzweil meets his critics. Searle has a chapter in the book in which he says at one point: "Suppose you took seriously the project of building a conscious machine. How would you go about it? The brain is a machine, a biological machine to be sure, but a machine all the same. So the first step is to figure out how the brain does it and then build an artificial machine that has an equally effective mechanism for causing consciousness. These are the sorts of steps by which we build an artifical heart. The problem is that we have very little idea of how the brain does it. Until we do, we are most unlikely to produce consciousness artificially in nonbiological materials" (72).

I agree with Kurzweil in seeing this as a fundamental concession to Kurzweil's reasoning. Searle admits that in principle a machine could replicate human intelligence if it could replicate the causal powers of the human brain. The only disagreement, then, is that Searle thinks our knowledge of the brain's working is too limited to permit this. Kurzweil is much more optimistic about future advances in neurobiology that will allow us to "reverse engineer" the brain and thus build "spiritual machines."

Darwinian conservatives should be skeptical about Kurzweil's vision, because they should be skeptical that human beings will ever have the perfect knowledge of how the brain works that would allow the creation of artificial intelligence with the complexity and flexibility of human intelligence. Human beings are uniquely endowed with a freedom of thought and action that comes from the emergent evolution of the soul in the brain. It is unlikely that we will ever know enough about the brain to artificially recreate the brain's causal powers in a machine.

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