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Should we select for genetic moral enhancement? A thought experiment using the MoralKinder (MK+) haplotype


By using preimplantation haplotype diagnosis, prospective parents are able to select embryos to implant through in vitro fertilization. If we knew that the naturally-occurring (but theoretical) MoralKinder (MK+) haplotype would predispose individuals to a higher level of morality than average, is it permissible or obligatory to select for the MK+ haplotype? I.e., is it moral to select for morality? This paper explores the various potential issues that could arise from genetic moral enhancement.

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  1. Underlying my paper is the statement by Mark Walker, “Should we accept the conjecture that at least some evil in the world is due to our biological nature?” [10].

  2. The author emphasizes that this is all purely conjectural—no known moral haplotype has yet been defined by science. The purpose of this paper is to explore the issues were such an MK+ haplotype (or its equivalent) were discovered.

  3. The reader should feel free to substitute her favorite moral rule or desirable virtuous action for the “do not steal” rule I use here to illustrate the MK+ haplotype. I think the reader will eventually agree that my arguments are not rule-specific or virtue-specific and they cross moral theory boundaries.

  4. By “moral inclinations,” I mean a child who has the same frequency of acting on desires and urges as the average 10-year-old does. I use the term “moral judgments” as does Borg: “judgments of the rightness or wrongness of acts that knowingly cause harm to people other than the agent” [5].

  5. Though I do not believe it has ever been proven, I presume that most of us are born with some amount of genetic moral potential or intelligence; otherwise, our moral teachings would fall on deaf ears (or the individual would be considered a sociopath).

  6. See footnote 4.

  7. See, for example, Agar [14], DeGrazia [15], Fukuyama [16], Green [17], Habermas [18] (see, in particular, chapters 6 and 7), Harris [19], McKibben [20], Parens [21], Walters [22], and the President’s Council [23].

  8. For a good summary of the various types of identity – biological, psychological, constitutive, and mind-embodiment, see David DeGrazia [15], especially chapter 7, “Prenatal Identity.”

  9. We also care about moral integrity because we care about personal reputation and/or internal desire consistencies.

  10. Though currently under dispute, there may be evidence that sociopathy is at least partially genetic (see the various commentaries to Linda Mealey in Brain and Behavior Science [32]). Suppose we could define an MK2 haplotype that would cause a child to be much less moral than normal, i.e., sociopathic. Would it be moral to permit parents to choose for this haplotype because of their desire to have a sociopathic child? I doubt there would be a market for this; generally we do not hear parents saying they wish their children were more evil, so I would doubt they would be clamoring for the MK2 haplotype as well, though there may be the rare set of parents who do so for criminal or dictatorial purposes, as noted in the main text.

  11. I thank an anonymous reviewer for raising this question.

  12. See, in particular, Chap. 10.

  13. Searle points out the problems with classical philosophical explanations of why we act based upon desires and beliefs by pointing out where the gaps arise, and claiming that rationality is in the gaps, not in the desires, beliefs, motives, intentions, and actions themselves [34]. Even with “universal standards of rationality and rational deliberation by agents, massive disagreements are still possible, indeed inevitable” [34, p. xv].

  14. Depending on one’s view of God’s interaction with human genetics, this comment may be debatable, but turns more on theology than moral philosophy. For example, might there be a divine reason that the penetration of the haplotype is not higher than 10%? Alternatively, might the random chance of evolution also have some reason we humans cannot divine not to have a higher penetration of the MK+ so far?

  15. Of course, although this thought experiment precludes that MK+ s have mentally negative effects, we would want to show through empirical observational studies that these children do not grow up to have higher rates of mental illness, addiction, family pathology, or other social/mental disorders because of social pressures associated with their principled stands in childhood.

  16. In some cases there are both. Take John F. Nash, Jr. who was awarded the Nobel Prize for economics in 1994 for his work in game theory. He is also the protagonist in the film “A Beautiful Mind.” Nash was both a genius achiever and a paranoid schizophrenic.

  17. For discussion about the public health approaches of this issue, see the seminal paper by Geoffrey Rose [37].

  18. Walters and Palmer make a similar argument regarding moral genetic interventions when they state, “many people, perhaps a majority in most societies where [a genetic intervention] is available, would accept this new technology. This majority, in turn, would help to create a new ethos that might well attract others who were initially skeptical” [22, p. 128].

  19. This analysis does not take into account the potential of additional synergies or dys-synergies, discussed below.

  20. See, for example, Smilansky [40] and Fotion [41].

  21. I am assuming in this discussion that there is no sharing of genetic information among parents in order to set up a reverse stigmata situation, where parents would initially choose to have their children socialize with other MK+ children only because they are identifiable and can aggregate them as such.

  22. Of course, it is also possible parents will figure out who is MK− through observing behavior and will not permit their children to play with them. In that case, we may have to await a generation or two of increasing penetration of MK+ for the “rising tide” to decrease the social divide.

  23. Granted, there may be a self-defeating quality to this, as pointed out by Parker: “The pursuit of the best possible, as opposed to the pursuit of the good, would be bound to lead to a life of dissatisfaction with any life as lived and to a constant drive for self-improvement” [17]. Countering this, religiously-oriented individuals could argue that it is only through approaching moral perfection that the time of the messiah might come (again).


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Thanks to Miller Brown and other members of the Hartford Ethics Group and the Santa Fe Ethics Group and to the anonymous reviewers of this journal for their review and comments on an earlier draft of this paper.

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Correspondence to Halley S. Faust.

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Faust, H.S. Should we select for genetic moral enhancement? A thought experiment using the MoralKinder (MK+) haplotype. Theor Med Bioeth 29, 397–416 (2008).

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  • Preimplantation genetic diagnosis
  • Selection
  • Morality
  • Genetic aristocracy
  • Liberal eugenics
  • Enhancement