The Future of Human Nature: A Symposium on the Promises and Challenges of the Revolutions in Genomics and Computer Science (Conference): Session One
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Series: Pardee Center Conference Series
Dates: April 10, 11, and 12, 2003
Location: Frederick S. Pardee Center for the Study of the Longer-Range Future, Boston University, Boston, MA
Session One (The Future of Human Nature: A Symposium on the Promises and Challenges of the Revolutions in Genomics and Computer Science (Conference): Session One)
Kenneth Lewes
Prolegomena
Welcome. We hope in the next few days you will hear more ideas and possibilities than you can possibly handle. Although we constantly hear about the benefits that the future will bring us, a coherent and broad view of technological progress is not readily available. Since we fully expect that some of the projections to be presented here will verge into the realm of science fiction, you might find it helpful if we suggest some ways of ordering and evaluating the welter of facts and speculation you will soon hear presented.
This conference was stimulated by an exchange of letters in 1933 between Albert Einstein and Sigmund Freud on the prospects of eliminating war from human experience. Einstein expressed a hope that human beings might be able to resist another regression to a primitive way of settling conflicts between nations. Freud, however, remained pessimistic for two reasons. He thought that the obstacles in the way of international agreement were too substantial to be overcome. But, more important, he thought that the impulse to destruction was inherent in human nature itself.
A consideration of current news, as well as a survey of recent cultural developments, suggests to some people that Freud may have been right. If so, it raises some difficult questions that are directly relevant to some of the presentations we will hear during this conference. Specifically, we must consider the complex relation of our progressive and increasing scientific knowledge of the world and its resulting technologies to what has up until now been our essential human nature. In these terms, is the recent astonishing progress in science and technology to be welcomed as the promise of a new Eden or dreaded as the threat of a terrible nightmare? Should human beings be entrusted with the power that science offers them? Or, on the contrary, have the age-old limitations on human power been a protection from our own capacities for hatred and destruction?
One source for hope is the possibility that science, in the near future, may be able to change human nature itself. This may happen by eliminating certain destructive traits or by enhancing others. Or it may occur because the abundance that technologies can offer us will make greed and competition no longer necessary for human survival. Yet even this hope brings along with it its own dread. The brave new world of the future may finally prove to be a horrifying dictatorship or a bland, intolerable state of boredom.
The very question of human nature, though abstract, impinges directly on our ability to imagine and plan for a future. Are there constraints placed on possible developments by essential components of human nature? Or perhaps the very nature of a human nature that transcends historical conditions is no longer a useful idea and has been rendered obsolete by the promises of science and technology. But if we discard the idea of an essential human nature, we are then left with no apparent way of measuring, judging, or controlling the future as it comes near. We are very far from being able to formulate these questions satisfactorily, let alone provide a useful answer to them.
Another difficulty that arises if we think that science can change human nature is trying to anticipate what will determine the shape and direction of scientific and technological progress. Science, of course, possesses its own internal determinants of what direction it will take. Nature and the world out there provide others. But equally powerful ones are generated by politics, social institutions, and economics. It is important to remember that scientific and technological progress, which seems to us so ineluctable, can be changed, redirected, or completely stopped by changes in the culture. The kinds of critical questions that once provided the themes for Victorian science fiction are turning into the reality of today. We must learn to look at them with a seriousness and steadiness that they never demanded of us before.
Charles Cantor
Human Evolution at the Crossroads
One hundred years ago, DNA was unknown. Today we know the entire DNA text of several human beings. Similar data exist on many model organisms. We have gained the ability to manipulate this text almost at will in organisms even as complex as mice. In the next few years our ability to do this will extend to humans. This means that we can now direct and accelerate human evolution along any paths we deem desirable. Hopefully, our wisdom in choosing these paths will match the power we have gained in using them. It seems an inevitable consequence of evolution that some species eventually reach that key threshold where they control their own evolution. This is now where we are.
The easy choices are to improve our quality of life by reducing the costs and discomforts of the major diseases that today affect mankind. Surely this is not controversial. However, there may well be differences of opinion whether the ultimate goal is a longer life span or a more disease-free existence at the current average life span. The hard choices are what human properties do we enhance and which do we leave as is. That we will shortly have such choices is astounding, but the implications are profound. Should we enhance our olfactory capabilities, offer the capability for regeneration; produce enhanced cognition; more efficient interfaces with computers, wireless communication? In my crystal ball, boredom could easily become the major scourge of an advanced human species; yet surely we will find ways to keep fascinated or engineer ourselves around this dilemma. Do we want to travel to far distances in the galaxy? Both boredom and radiation sensitivity will need to be overcome to make this feasible.
In my talk I will give an overview of the methods currently available to direct human evolution: their current limitations, and the likely time scales needed to overcome these limitations. But based on past experience, any projections I make of the timing and magnitude of directed human evolution will be far too conservative. I will illustrate this dilemma with the current explosion in the rate of discovery of the genes that underlie complex human disease.
If I had given this talk ten years ago, my conclusions would have been the opposite of those I come to today. I would simply have said, “None of this will ever happen. We will never allow it.” Many individuals and institutions today share my previous pessimism. Both the CIA and various think tanks for defense intelligence are concerned about the risk that technology will destabilize society as we know it. At the other end of the spectrum, there are the venture capitalists who are concerned with how they are going to make money on the new technology. Everybody tends to see these developments from his own narrow perspective, but the time has come for us to try to think outside the box. In my own thinking on this matter, I have found modern fiction to be very provocative and eye-opening.
A major cornerstone of modern biology is evolution. In its classical formulation, the fittest species survive. This notion of fitness is really quite a boring idea. All that matters is the number of fertile offspring. We must remember, however, that evolution takes place in a fluctuating environment and is not a continuous, gradual process. It proceeds in fits and starts. That other thing to remember is that the present is not the termination and end-all of the evolutionary process. Not only has evolution not stopped, but it probably is about to go much faster.
All of us—every species—is essentially a convolution of genes we are dealt at birth and the environment we experience starting at conception. Any attempt to predict on the basis of genes alone—or the environment alone—is doomed to failure. This has always been true, but the notion of evolution is changing. We are still interested in the best genes for a given environment, but we now control the environment. And, as a result of sequencing the human genome and the growth of genetic engineering, we now control the genes. Our species is no longer simply buffeted by the environment; it now controls it. That is the power we now have. In other words, natural selection no longer determines the evolutionary process; artificial selection does.
One hundred years ago, DNA was unknown. Fifty years ago, before Watson and Crick, we did not know that genes were DNA. Today, we have the entire DNA sequences for some species and understand many of their rules. What will our knowledge and technology be like in fifty years? Based on my own prediction and experiences, I would say that any prediction, even the most outlandish, will prove too conservative. The Human Genome Project gave us a map with an interstate highway system on it that you could not really use to find anything specific. Now we can find anything we want, and we can do it rapidly.
In my own organization, Sequenom, we discover genes that underlie complex human traits and common, complex human diseases that affect everyone. In the last eighteen months, we have done more human genetics than has been done in the history of the planet. The automated system we have developed makes up to two hundred thousand human genetic measurements a day. Using it, we have discovered genes that underlie many of the diseases we care about: skin cancer, cardiovascular disease, breast cancer, adult diabetes, HDL, osteoarthritis, lung cancer, schizophrenia. We are finding genes that account for about twenty-five percent of each of these diseases. An indication that we are on the right track is the fact that, using blind studies, we have rediscovered genes that we already knew were implicated in several diseases.
A major implication of these developments is that medicine will have to change in dramatic and essential ways. This is because the inherited differences that predispose us to disease will have to be addressed. This will require individualized therapy. At least half the targets we find responsible for human disease are not addressable using traditional therapies. Instead the medicine of the future will seek to contain disease using gene therapy. Medicine will move from a reactive mode to a preventive one. The least controversial of the new gene therapies is somatic, where a virus or stem cells are used, but do not enter the germ-line and so are not inherited. Their effect is merely palliative. They disappear when the organism dies. More problematic, however, because it is permanent and inheritable, is the use of embryonic stem cells. These changes are passed on to the offspring.
I think it is only a matter of time before human cloning and human germ-line gene therapy become fairly standard. There are, however, cultural traditions standing in the way of this development. Generally speaking, European traditions are suspicious of, if not hostile to, genetically modified organisms. On the other hand, China and India are extremely enthusiastic about the possibilities. In some provinces in northern India, the sex ratio at birth is four males to three females. The premier of China is on record as having said, “We will use genetic engineering to change our people to reduce our health care costs.” It will not be possible to stop such development. The driving force behind them is economics.
I do not know if it will be possible to develop a uniform set of rules regulating this kind of technological development. But the person who directs the selection is potentially the survivor. Nevertheless, it is not so difficult to make predictions about some of the things we should not do. First, we must be careful not to go down the road to homogenization. Evolution always favors diversity, because it allows for survival in case the environment turns sour. Homogenization is also very boring, and I think we have to be very afraid of being bored in the future.
If one of us could take a trip forward two hundred years in a time machine, I am not sure he would be able to recognize humans, they would have changed so utterly. We have the tools today not just to control evolution, but to speed it up in a massive way. The cat is out of the bag. Evolution is in our hands. I only hope we have the wisdom to use it wisely.
Lee Silver
The Inevitability of Human Genetic Enhancement and Its Impact on Humanity
Incredible advances in reproductive and genetic technologies will someday provide prospective parents with the ability to enhance their embryos so that their children can be born with genetic advantages that they themselves do not carry. This technological leap into “reprogenetics” will be the most important in the history of humankind because it could change the very nature of the human species. There is much debate about both the science and the ethics of human germ-line genetic engineering. Some scientists claim it will never be possible to develop the technology for use in a safe way. Many bioethicists believe that even if safety concerns are overcome, it is still unacceptable to “tamper” with a child’s genes, even to combat disease. I will argue that recent scientific advances leave no doubt about future technical feasibility. I argue, as well, that nearly all of the objections raised by bioethicists are logically inconsistent or based on narrow religious beliefs. Instead, I believe the fundamental ethical dilemma is rooted in the conflict between individual autonomy and social equality. Principles of social equality might lead a society to reject the use of a technology that could greatly widen the gap between affluent and nonaffluent segments of humanity. In America, however, principles of individual autonomy and noninterference into private family matters are paramount. And the natural desire of parents to give all possible advantages to their children will be the driving force of reprogenetics. Each individual use of reprogenetic technology may have no effect on society at large. Indeed, in affluent societies, the technology could become quickly affordable to the middle class, and may even be promoted institutionally as a way of reducing long-term societal health care expenses. But as genetic enhancements accumulate from one generation to the next in affluent countries, the gap between affluent and nonaffluent countries could widen unimaginably until our species commonality is irrevocably severed. The only alternative seems remote today and it may never be viable: a pan-global health maintenance system which provides all human children with the same genetic protections and the same opportunities for health, happiness, and success.
In a liberal, democratic society, like the one we live in, individual parents have the choice about what they do with their children. For example, they may spend $150,000 to send their children to first-class universities, all for the chance of providing their children with an advantage to succeed in life. In the near future, we will see the technology which depends on our knowledge of DNA combine with reproductive technology to give us reprogenetics, reproductive and genetic technology, which will be able to ensure or prevent the inheritance of particular genes in children. While there is a danger that governments may tell people what to do with their children, it is more likely that individual parents will be deciding what is best for them.
In the past, many eminent biologists doubted that genetic manipulation of the kind we are discussing would ever be possible, primarily because of the infinitesimal sizes involved. We now know that it can be accomplished, and, in several cases, already is. Other doubts have arisen based on the margin of error involved. Advances in technology, however, allow us to operate within acceptable risks. In fact, very soon reproductive technology will operate at levels of risk below that of natural sexual intercourse. Other doubts arise from religious and philosophical objections to reproductive technologies and involve vague ideas about the human soul or hesitations about taking on responsibilities that traditionally have been left to divine power or the operations of chance.
Even people who espouse these philosophical objections are less clear when they are faced with the specific choices that will become available to them. In the United States there does not seem to be a consistent preference for the gender of children; in other places in the world, there is. Most people, however, agree that the prevention of disease in children is an appropriate aim. It is also only natural for parents to wish to endow their children with advantages, especially those that will affect their children’s economic success in later life.
There are several common examples of genetic manipulation that occurred long before the discovery of DNA, which people accept almost as a matter of course. The diversity of breeds of dogs with different physical and mental characteristics, all from a single species of gray wolf, is a case in point. Another is the development of modern corn from a weed that once grew in Mexico. In addition, wool does not exist naturally, but was bred over centuries from a goat that was hairy. Recently, more sophisticated engineering has made it possible to increase the size of the cerebral cortex in mice. It is rapidly becoming possible to control the distribution of certain traits that affect future economic success for individuals. Height is an example. Should parents be able to determine characteristics like these in their children? The natural distribution of traits is inherently unfair. So is it unfair to control the distribution by choice and planning? Similar arguments apply to susceptibility to disease, as well as to athletic, artistic, or intellectual ability. Americans will ask, “Why can’t I give my children advantageous genes that other children get naturally?” The issue boils down to who will do the selection: God, nature, chance, the government, or parents. Parents should be able to choose what they want for their children as long as they do no harm to them.
It can still be asked if we are going to change human beings in an essential way. With respect to the changes we have been discussing, we are not really changing human nature, but only the frequencies of alleles in the population. Two things basically define us as humans. One is the way we look, the other the way we think. It is unlikely that the appearance of human beings will change in the future beyond small, superficial characteristics, since it is essential that human beings continue to find each other attractive. As for mental abilities, it is unlikely that natural selection itself will change that, since smarter people do not have more babies.
The issue of who will choose whether to enhance children genetically is very difficult. At one extreme, the government can provide such services to all its citizens. At the other, it could be left up to individual parents and their economic condition. It is most likely that in the future there will be a widening gap between people, especially those in rich and poor countries. Generation after generation of genetic enhancements could accumulate until humanity finally separates in distinct species. This, however, is not a scientific question, but a social and political one. Scientists do not really control technology. It is people and governments who use scientists and determine how all these technologies will be used.
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