7. What About the Human Mind?

The human mind is by far the most wide open frontier for science, mainly because it is still so profoundly mysterious, in spite of all the advances of modern neuroscience. In his bestseller "Listening to Prozac" the psychiatrist Peter Kramer portrayed us as marching inexorably toward a Brave New World in which we can fine-tune our moods and personalities with drugs. This vision is a fantasy. What the scientific literature actually says is that Prozac and other so-called wonder drugs are no more effective for treating depression and other common emotional disorders, statistically speaking, than the more primitive antidepressants, such as imipramine, which themselves are no more effective, statistically speaking, than talk therapy.

Kramer was on firmer ground when he said, at the end of his book, that our understanding of our own minds is still "laughably primitive." The question is, when, if ever, will that situation change? Last June I attended the annual meeting of the American Psychiatric Association in New York City, along with almost 20,000 other people. There were therapists there who still admit to being Freudians. And why not? No theory or treatment for the mind has been shown to be significantly better than psychoanalysis. Cheaper, maybe, but that's not a scientific criterion. The hot, up-and-coming treatment for depression, and even schizophrenia and other disorders, is electroshock therapy, which can cause severe memory loss and other side effects. That does not seem like a sign of progress to me. The science of mind has�in certain respects�become much more empirical and less speculative since the days of Freud. We have acquired an amazing ability to probe the brain, with microelectrodes, magnetic resonance imaging, positron-emission tomography and the like. Maybe all this work will culminate in a great new unified theory of and treatment for the mind. But I suspect it won't. What I think neuroscience can and will accomplish is correlating specific physiological processes in the brain to specific mental functions�such as memory, perception and so forth�in ever-finer detail. This kind of nitty-gritty, empirical research should have profound practical consequences, such as providing better ways to diagnose and treat mental illness.

But neuroscience will not deliver what so many philosophers and scientists yearn for. It will not solve all the ancient philosophical mysteries relating to the mind�the mind-body problem, the problem of free will, the solipsism paradox, and so on. Nor will neuroscience demonstrate that consciousness is somehow a necessary component of existence, which is an idea that is alluring not only to New Agers but also to scientists and philosophers who should know better. This is a material world. We have all seen bodies without minds, but only psychics and psychotics have seen minds without bodies. The universe existed for billions of years before we came along, and it will continue to exist for eons after we and our minds are gone.

Psychologists, social scientists, neuroscientists and others seeking the key to the human psyche will periodically seize upon some "new" paradigm as the answer to their prayers. One paradigm that proves perennially alluring is Darwinian theory, which in its latest incarnation is called evolutionary psychology. But as crucial as it is for understanding life in general, Darwinian theory does not provide very deep insights into human nature, as I tried to show in "The New Social Darwinists," published in the October 1995 Scientific American.

Darwinians often complain that their views of human nature are rejected because of the continuing dominance within academia of left-leaning scientists, who for political reasons insist that humanity is infinitely malleable. That's just not true. If evolutionary theory had turned out to be a truly powerful paradigm for explaining human behavior, it would have been embraced by the scientific community. Noam Chomsky has said that we will probably always learn more about human nature from novels than from science. I agree.

8. What About Applied Science?

Some scientists grant that the basic rules governing the physical and biological realms may be finite, and that we may already have them more or less in hand. But they insist that we can still explore the consequences of these rules forever and manipulate them to create an endless supply of new materials, organisms, technologies and so forth. Proponents of this position�many of whom adhere to a quasi-scientific cult called nanotechnology�often compare science to chess. The rules of chess are quite simple, but the number of possible games that these rules can give rise to is virtually infinite.

There's some validity to this position. Applied science obviously has much further to go, and it is hard to know precisely where it might end. That fact was vividly demonstrated by the story of Dolly the cloned lamb; many scientists had believed that cloning from adult cells was impossible.

But I still believe�surprise, surprise�that the limits of applied science are also coming into sight. Let me offer several examples. It once seemed inevitable that physicists' knowledge of nuclear fusion�which gave us the hydrogen bomb�would culminate in a cheap, clean, boundless source of energy. But after 50 years and billions of dollars of research, that dream has now become vanishingly faint. In the last few years, the U.S. has drastically cut back on its fusion budget, and plans for next-generation reactors have been delayed. Now even the most optimistic researchers predict that it will take at least 50 years before we have economically viable fusion reactors. Realists acknowledge that fusion energy is a dream that may never be fulfilled: the technical, economic and political obstacles are simply too great to overcome.

Turning to applied biology, the most dramatic achievement that I can imagine is immortality. Many scientists are now attempting to identify the precise causes of aging. It is conceivable that if they succeed in pinpointing the mechanisms that make us age, researchers might then learn how to block the aging process and to design versions of Homo sapiens that can live indefinitely. But evolutionary biologists suggest that immortality may be impossible to achieve. Natural selection designed us to live long enough to breed and raise our children. As a result, senescence does not stem from any single cause or even a suite of causes; it is woven inextricably into the fabric of our being.

One might have more confidence in scientists' ability to crack the riddle of senescence if they had had more success with a presumably simpler problem: cancer. Since President Richard Nixon officially declared a Federal "war on cancer" in 1971, the U.S. has spent more than $30 billion on research. But overall mortality rates have remained pretty much flat since 1971 and in fact for the last 50 years. Treatments are also still terribly primitive. Physicians still cut cancer out with surgery, poison it with chemotherapy and burn it with radiation. Maybe someday all our research will yield a "cure" that renders cancer as obsolete as smallpox. Maybe not. Maybe cancer�and by extension mortality�is simply too complex a problem to solve.

Paradoxically, biology's inability to solve certain important problems may be its greatest hope. Harvey Sapolsky, a professor of social policy at MIT, touched on this paradox in an article for Technology Review back in December 1995. He noted that the major justification for the funding of science since the Second World War was national security�or, more specifically, the Cold War. Now that scientists no longer have the Evil Empire to justify their huge budgets, Sapolsky asked, what other goal can serve as a substitute? The answer he came up with was immortality. Most people think living longer, and possibly even forever, is desirable, he pointed out. But the best thing about making immortality the primary goal of science, Sapolsky said, is that it is almost certainly unattainable, so scientists can keep getting funds for more research forever.

9. The End of Science Is Itself an Ironic Hypothesis

I admit that, as a journalist, I'm overly fond of playing gotcha games. In my book, for example, I describe an interview with the great philosopher Karl Popper, who argued that scientists can never prove a theory is true; they can only falsify it, or prove it is false. Naturally I had to ask Popper, Is your falsifiability hypothesis falsifiable? Popper was 90 then, but still intellectually armed and very dangerous. He put his hand on my hand, looked deep into my eyes, and said, very gently, "I don't want to hurt you, but it is a silly question."

Given my style of journalism, I guess it's only fair that some critics have tried to give me a taste of my own medicine, pointing out triumphantly that my own end-of-science thesis is an example of ironic theorizing, since it is ultimately untestable and unprovable. This argument was put forth in the review of my book in The Economist, American Scientist and elsewhere.

But to paraphrase Karl Popper, "This is a silly objection." Compared to atoms, or stars, or galaxies, or genes or other objects of genuine scientific investigation, human culture is ephemeral; an asteroid could destroy us at any moment and that would bring about the end not only of science but also of history, politics, art�you name it. So obviously any prediction about the future of human culture is an educated guess, at best, at least compared to nuclear physics, or astronomy, or other disciplines that prove certain facts beyond a reasonable doubt.

But just because we cannot know with certainty what our future is does not mean that we cannot make cogent arguments in favor of one scenario over another. I think my end-of-science scenario is much more plausible than the ones that I am trying to displace, in which we keep discovering profound new truths about the universe forever, or arrive at an end point in which we achieve perfect wisdom and mastery over nature.

10. The Lack-of-Imagination Argument

Of all the criticisms of my thesis, the one that really gets under my skin is that it reflects what Newsweek called a "failure of imagination." Actually, it is all too easy to imagine great discoveries just over the horizon. Our culture does it for us, with TV shows like Star Trek and movies like Star Wars and ads and political rhetoric that promise us tomorrow will be very different from�and almost certainly better than�today. Scientists, and science journalists, too, are forever claiming that a huge revelation or breakthrough or holy grail awaits us just over the horizon. I have to admit, I've written my share of such stories.

What I want people to imagine is this: What if there is no big thing over the horizon? What if what we have is basically what we are going to have? We are not going to invent warp-drive spaceships that can take us to other galaxies or even other universes. We are not going to become infinitely wise or immortal through genetic engineering. We are not going to discover the mind of God, as the British physicist Stephen Hawking once put it. We are not going to know why there is something rather than nothing. We'll be stuck in a permanent state of wonder before the mystery of existence�which may not be such a terrible thing. After all, our sense of wonder is the wellspring not only of science but also of art, and literature, and philosophy, and religion.

One final point. I've been accused by some critics�such as Phil Anderson�of having a hidden anti-science agenda. That's ridiculous. I became a science writer because I love science. I think science is the most miraculous and noble and meaningful of all human creations. My conviction that science is ending is deeply disturbing to me, because I can't imagine anything better for humanity to do than to try to figure out what we are, where we came from and where we are going. I sincerely hope that in my lifetime some scientist�maybe even someone reading this posting�will discover something as important as natural selection or quantum mechanics or the expansion of the universe, something that spawns a whole new era in pure science and proves me wrong. But I also sincerely believe that isn't going to happen.