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July 01, 2009 (Vol. 29, No. 13)

Therapy and Enhancement: Is There a Moral Difference?

Drawing a Principled Line between the Two Is Complicated, if It Even Exists

  • Shifting Lines in the Sand

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    Patrick Lin, Ph.D.

    Some scholars have reasonably objected to, or at least raised difficulties with, the distinction between therapy and enhancement. For instance, how should we think about vaccinations: are they a form of therapy or are they an enhancement of our immune system? On one hand, a vaccination seems to be an enhancement in that there is no existing pathology it is attempting to cure, merely a possible or likely pathology we wish to avoid; but aren’t we drawn to declare it as some form of therapy—perhaps preventative therapy—given its close association with medicine as we know it?

    Another dilemma: if a genius were to sustain a head injury, thereby reducing her IQ to merely the average or species-normal range, would raising her intelligence (through some future drug, surgery, or technology) back to its initial genius level count as therapy or enhancement? Either one would seem plausible, but is there a nonarbitrary reason for answering the question either way? If an enhancement, then how do we explain the difference between that and a clearer case of therapy in which we return an average person who sustains a head injury back to the normal  IQ range? And if we need to rely on fuzzy concepts such as “average” and “species-typical”, then it’s even more difficult to defend the therapy-enhancement distinction.

    One more dilemma: the U.S. military is increasingly prescribing antidepressants to soldiers in combat to alleviate post-traumatic stress as well as stimulants to counteract sleep deprivation. Should we view those actions as creating a more effective, level-headed soldier (an enhancement) or returning the soldier to the initial normal state of combat readiness (a therapy)?

    These and many other cases point to serious difficulties in drawing a principled line between therapy and enhancement.  That does not mean, however, that we should abandon the distinction quite yet.  For one thing, if we cast aside the distinction, it may be too easy to argue that all forms of human enhancement are morally permissible—thus ending the debate before it even fully develops—given that things we count as therapy are permissible and that there’s no relevant difference between therapy and enhancement.

    But more generally, the challenge of clearly defining and delineating a concept exists for virtually any given concept: What is knowledge? What is art? What is a person? How is physics different from chemistry or biology? That is to say, just because we cannot precisely draw a line does not mean that a line does not exist or concepts are useless.

    In philosophy, there is a famous sorites puzzle called The Paradox of the Heap:  Given a heap of sand with N number of grains of sand, if we remove one grain of sand, we are still left with a heap of sand (that now only has N-1 grains of sand). If we remove one more grain, we are again left with a heap of sand (that now has N-2 grains). If we continue to remove grains of sand, we see that there is no clear point P where we can definitely say that a heap of sand exists on one side of P, but less than a heap exists on the other side. In other words, there is no clear line between a heap of sand and a less-than-a-heap or even no sand at all.

    However, the wrong conclusion to draw here is that there is no difference between them, or that the distinction between a heap and no heap should be discarded.  Likewise, it would seem premature and fallacious to conclude that there is no difference between therapy and enhancement, or that we should dispense with the distinction.

    Of course, it may ultimately be the case that there is no moral difference between the two, but we cannot arrive at it by merely observing that there is no clear defining line or that there are some cases that make the line fuzzy. As with heap, the terms therapy and enhancement may simply be vaguely constructed and require more work to locate. These open questions have elusive answers, but they persist at the center of the human enhancement debate and so deserve our attention.

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