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This staff working paper was discussed at the Council's April 2002 meeting. It was prepared by staff solely to aid discussion, and does not represent the official views of the Council or of the United States Government.

Staff Working Paper

Distinguishing Therapy and Enhancement

Technologies based on advances in genetics, pharmacology, neuroscience and related fields of biomedicine have the potential to help the sick and provide relief to the suffering, but they also have the potential to be used in ways that lack clear medical benefits or may even prove to be improper or unethical. Rejecting these new technologies wholesale would in many cases mean unwisely foregoing genuine medical benefits, but accepting them wholeheartedly could in many cases pose significant moral and social harms that we should work to avoid.

We need, therefore, to find ways to distinguish between proper and improper uses of these new technologies. A frequently suggested basis for telling them apart is the distinction between those uses of new biomedical technologies that aim at therapy and those that aim at non-therapeutic enhancement. Drawing lines between therapy and enhancement may sound like a straightforward task in the abstract, but in practice the difference is often far from clear.

This working paper explores some sources of the ambiguity involved, but argues for the importance of nonetheless seeking out a distinction between therapy and enhancement.

A. The Ambiguity of the Therapy/Enhancement Distinction
A therapy, roughly defined, is a treatment for a disorder or deficiency, which aims to bring an unhealthy person to health. An enhancement is an improvement or extension of some characteristic, capacity, or activity. Both definitions assume at least some general sense of a human norm, which individuals must either be helped to reach, or which they might be aided in surpassing (and on the problems of this "norm," more below). The distinction between therapy and enhancement is hard to articulate for three principal reasons: 1) they are not mutually exclusive, 2) the activity involved is often the same, and 3) the standard of health and "improvement" against which the difference between therapy and enhancement might be measured can be very hard to define.

First, most if not all therapies are also enhancements, though not all enhancements are therapeutic, in the sense defined above. It is therefore not possible to simply classify applications of biotechnology into the categories of "therapy" and "enhancement," since the categories overlap. To avoid this difficulty, the term "enhancement" is generally used only when the activity in question is not medically therapeutic (or, in other words, it used to mean "non-therapeutic enhancement"). Even under this narrower definition, however, the term "enhancement," contains its own ambiguities. When referring to a human function, does enhancing mean making more of it, or making it better? Does it refer to bringing something out more fully, or to altering it qualitatively?

And even if we could clarify the meaning of the term somewhat, we would of course still be left with the question of the difference between therapy and enhancement as it applies to particular applications of biotechnology. The question would remain because the activities we seek to describe do not themselves provide the distinction between therapy and enhancement. This is the second major cause of the ambiguity we confront. In both therapy and enhancement, the activity in question involves an extension or augmentation of a certain human capacity. The difference between them is not in the activity, but rather mostly in the starting condition of the person who is treated, relative to the "norm."

When the human capacity in question is severely abnormal and the individual involved is harmed by that abnormality -- say, a severe hyperactivity that may be treated by Ritalin, or a pituitary deficiency that may be helped by human growth hormone, or a heritable disease that might someday be avoided through the insertion of synthetic genes -- the augmentation is considered therapeutic. When the capacity is not particularly degraded to start with and the augmentation is undertaken for the sake of improvement alone -- as with the use of Ritalin to improve the concentration of Ivy League test-takers, or the use of growth hormones to beat back the aging process, or (someday) genetic engineering to improve endurance in athletes -- it may be considered a non-therapeutic enhancement.

These examples, intentionally drawn from the contemporary biotechnological revolution, demonstrate that the same process or use of technique could be described as either therapy or enhancement, depending largely on the starting condition of the affected individual. Therapy suggests bringing one up to the level of adequate human health, capacity, or performance; while enhancement suggests taking one up beyond one's existing level of health, capacity, or performance. The question that defines the difference between them, therefore, is whether one’s existing capacity or level of performance is adequate, but this is a vague and complicated question. Adequate for what, and by what measure?

This brings us to the third, and perhaps the most serious, source of the ambiguity of the line between therapy and enhancement. The standard against which we might determine whether a given procedure aims at therapy or enhancement – which may be roughly described as the standard of health -- is notoriously difficult to pin down.

This is so for several reasons. First, there has long been some question about just what the definition of health, or the goal of medicine, ought to be. Some argue that health is, to quote the famous World Health Organization definition, "a state of complete physical, mental and social well-being." By this definition, almost any enhancement may be defined as health-promoting, and hence "therapeutic," if it serves at least the mental well-being of the enhanced individual by making him happier. Others put forward a narrower definition of health, which proposes more specific goals for medicine. For instance, Norman Daniels has written that "disease and disability are seen as departures from species-typical normal functional organization or functioning," so that health is defined by species-typical capacities. Daniels draws from this definition a rough sense of what the purpose of therapy or healing is: "to maintain, restore, or compensate for the restricted opportunity and loss of function caused by disease and disability." Successful therapy, therefore, "restores people to the range of opportunities they would have had without the pathological condition or prevents further deterioration." In this sense, therapy makes people whole, while enhancement alters the whole.

This understanding of health takes it for granted that people enter the world with different natural endowments, and argues that the role of medicine is not to equalize that distribution (which may be a recipe for endless frustration) but to prevent individuals from falling below that general distribution, and from suffering pain and serious discomfort.

But even within this narrower definition, some problems present themselves. While in some cases -- for instance, a chronic disease or a serious injury -- it is fairly easy to point to a departure from the standard of health, other cases defy simple classification. First of all, most human capacities fall along a continuum, or a distribution curve, and individuals who find themselves near the lower end of the normal distribution may be considered disadvantaged and therefore unhealthy in comparison with others. Of course, some who are "average" may also consider themselves disadvantaged in comparison with some who are near the top of the distribution. At what point, then, do we determine that an individual is in need of therapy? And is it reasonable to make such a determination based mainly on a comparison with others, or with a human average?

Secondly, the distribution curve of any given human characteristic may tend to change as biomedical advances introduce new therapies, or even just as living conditions change. As the bottom end of the curve is raised up, the average, too, moves higher, leaving different people at the bottom. Thus, the standard of health proves not to be thoroughly fixed in place in some respects, and therefore may not be the best measure of the distinction between therapy and enhancement.

Even regarding capacities that do not have a wide distribution, or where the average stays put, a change "upwards" need not necessarily be an enhancement. More is not necessarily better. Everything depends upon an independent norm.

For all of these reasons, the line between therapy and enhancement is very hard to specify. Yet the blurring of that line may still be a real concern, and certain sorts of enhancements may be inappropriate, morally questionable or even dehumanizing.

B. Why Worry About Enhancement?
The distinction between therapy and enhancement is important for several general reasons. The first, and perhaps most familiar, is based upon an appeal to excellence, but opens up a far broader set of concerns. In activities developed to strain the limits of what a human being can do (like running a race), enhancements change the background against which excellence is admired. In a race in which all the participants have used performance-enhancing drugs, we may find it easier to admire the chemists than the athletes, and the meaning of the accomplishments involved will be greatly diminished. This is in essence an argument about integrity in the pursuit of excellence, and as such may have limited force. But we begin with it because it is a familiar example that points us to a more serious and general concern about the separation of human effort from human accomplishment.

This second concern has to do with the relation of means and ends, of efforts to deeds. The means by which certain improvement or changes are sought are often essential to the goals pursued. Teaching a child to wait patiently and sit quietly does more than simply keep a classroom orderly. It also gives the child some experience in self-control and teaches him or her the importance of restraint. Medicating the child to sit quietly would have the same effect on classroom order, but might not have the same effect on the child. The means by which behavior is accomplished matters, because the performer is distinct from his or her performance. A good grade on a difficult test has a different meaning when it is accomplished by strenuous effort and study than when it is accomplished with the aid of concentration-inducing pharmaceuticals (just as it is when accomplished by cheating). Self-esteem means something different when it is the product of work and accomplishment than when it is the product of cosmetic enhancements.

Human life is an ongoing experience, not a static condition, and so the way that ends are reached -- the experience of change -- often matters at least as much as the ends themselves. Separating improvement from the experience of effort and exertion could tend to undermine the meaning and importance of improvement, and encourage a mechanistic understanding of human life that would be both inaccurate and dehumanizing. Such an understanding of humanity could also undermine personal responsibility, and diminish the significance of human accomplishments. If self-improvement were easy, it would not be so satisfying. Artificial enhancement may well prove to be a barrier to genuine self-improvement.

This point raises an important difference between enhancement mediated by biotechnology and enhancement advanced by social, cultural or educational means. The first sort tends to act on the body of the individual involved, while the second addresses itself to the individual's character, experience and psyche. But of course the line between the two is not always clear.

A third concern involves the risk of distorting the meaning of human normality. If enhancements of the sort made possible by modern biotechnologies were to become commonplace, they could surely affect the very standard by which individuals judge the need for enhancement. Presumably, a primary reason for seeking such enhancement is the sense that one is below average with regard to some ability or characteristic. But by the very act of enhancement, we raise the average, and therefore may increase the pressure on others to seek the same enhancement (which in turn would only exacerbate this effect.) In the process, any distinction between necessary therapy and optional enhancement will be only further obscured, as more of what was optional yesterday will come to seem essential. As so often happens with new technologies, our new powers will create new needs.

Fourth, the widespread use of such enhancements might also tend to confuse our priorities. When we find ourselves armed with the power to do something new, that thing suddenly begins to appear more important. If some individuals use new technologies to improve their appearance, or their height, or their mood, then others, seeing themselves disadvantaged, will place great importance on obtaining the same enhancements. In the process, those non-therapeutic uses of biotechnology -- often uses that tend to focus on shallow or cosmetic matters -- will make shallow cosmetic matters even more important to us than they already are. This may also tend to blind us to the substance of the changes we undertake in ourselves, as the standard by which we might measure change fades away. After all, if we cannot tell enhancement from therapy, who is to say that we can tell enhancement from degradation?

Finally, the distinction between therapy and enhancement is also important in the effort to contain the medicalization of various arenas of life, and to determine what problems and challenges are (or are not) properly conceived of in terms of medicine. By distinguishing the proper reach of medicine -- say, for treating clinical depression but not shyness, or severe disfigurement but not slight imperfection -- we will be better able to discern its proper limits.

We see, therefore, the importance of distinguishing therapy from enhancement, even as we see the difficulties involved in doing so. The question that now confronts us is how such distinctions can be made, and in what standard they may be grounded.

In the following section, we provide a few brief examples of specific technologies that challenge us to draw a distinction between therapy and enhancement.

C. Examples of Enhancement

1. Therapeutic and Enhancement use of human growth hormone
Recent biotechnological research and development has made possible the production and sale of recombinant human growth hormone (rhGH). Some young children who are of short stature with reference to the appropriate height/age curve because of a deficiency of human growth hormone, can be restored to more "normal" height through injections of rhGH. This would meet the definition listed above as therapy. However, administration of rhGH to young children who are within the "95% envelope" on the appropriate height/age curve, in an attempt to make them taller, would raise the question of whether this was enhancement.

2. Exploration of human brain and nerve-computer link
Miniaturization of electronics is another current technology trend. Professor Kevin Warwick at the University of Reading in the U.K. had a second generation nerve cell-computer system interface chip implanted between his left elbow and shoulder in March 2002.

Based on plans described in an interview with Wired magazine in 2000, wires extending from the glass-enclosed chip will make direct contact with major nerves running from Warwick's brain to his hand. Nerve signals as Warwick moves his hand will be transmitted from the chip to a computer and stored for playback. Warwick plans to test whether the recorded nerve signals, when fed back to the implant by the computer, can cause the same motion of his hand.

Warwick has multiple questions that he would like to investigate with this self-experiment. In the same Wired interview, he outlined several of them as follows:

"I am most curious to find out whether implants could open up a whole new range of senses. For example, we can't normally process signals like ultraviolet, X-rays or ultrasound. Infrared detects visible heat given off by a warm body, though our eyes can't see light in this part of the spectrum. But what if we fed infrared signals into the nervous system, bypassing the eyes? Would I be able to learn how the perceive them? Would I feel or even "see" the warmth? Or would my brain simply be unable to cope. We don't have any idea -- yet."

Would a new human capability to "see" infrared be an enhancement?

3. Genetic
Biotechnological research and development has isolated the gene for human erythropoietin (EPO) and produced large amounts of recombinant EPO protein. EPO is a hormone that stimulates the production of red blood cells, so it is used to treat kidney dialysis patients and others who suffer from anemia (therapy). However, EPO has also been used by non-anemic athletes in attempts to improve performance in competitive events where a lot of oxygen is required by the muscles (cycling, for example). Would this use of EPO be enhancement?

DNA vector systems designed to produce human EPO when injected into human cells are being developed as an alternative therapy for kidney dialysis patients. Athletes may be tempted to get injections of EPO expression vectors into their muscles as they prepare for sports competitions. Would this use be enhancement?

4. Neuropharmacological
The drug Ritalin is widely prescribed and used in the treatment of Attention Deficit Disorder (ADD). Diagnostic criteria for ADD include "trouble concentrating" and "overactivity" in motor functions. Since there are difficulties in specifying the human norm of "ability to concentrate" and "overactivity in motor functions," the diagnosis of ADD is more subjective than other medical diagnoses. Since there is subjectivity in diagnosis and variable degrees of "trouble concentrating," defining the limits of this disorder and thus determining those for whom a Ritalin prescription is appropriate therapy is particularly difficult.

In addition, however, students who did not meet even the fuzzy diagnostic criteria for ADD discovered that taking Ritalin seemed to help then concentrate during exams. Is this use of Ritalin to be considered enhancement? Does it differ ethically from drinking a cup of coffee or tea before an exam, thereby using caffeine to stay more alert during the exam?

Other possible examples of enhancement
1. Germ line genetic engineering to improve the genetic characteristics of future generations.

2. Aging research that seeks substantial increases in the maximum human life expectancy.

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