Human enhancement and human diversity : the need for a coordinated approach to enhancement technologies




Gyngell, Christopher Allan

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In this thesis I develop a novel perspective on human enhancement and its moral and philosophical implications. I begin by describing the scientific developments that have ignited a debate within bioethics on human enhancement and reviewing the ways in which the concept of enhancement has been analysed in the philosophical literature. I then describe some of the ethical arguments that have been proposed both for and against human enhancement. Human enhancement technologies have the potential to benefit not only individuals, but also human groups - such as our communities and our species. In this thesis I show how these two potential uses of enhancement technologies often conflict. The use of cognitive enhancement technologies to make individuals smarter may reduce our collective ability to solve problems; the use of life extension technologies to increase the lifespan of individuals may reduce the long term persistence of the species; and the use of genetic enhancements to improve individual wellbeing may make society as a whole worse off. In Chapter 1 I argue that the use of genetic enhancement technologies to benefit individuals could reduce valuable forms of genetic diversity and undermine the continued survival of the human species. In Chapter 2 I develop this idea further to show that the rational use of particular reproductive technologies by individuals could have a negative effect on society as a whole, including future generations. I argue this provides a plausible prima facie reason to restrict access to particular enhancement technologies. In Chapter 3 I discuss the use of reproductive technologies to screen against disability. I argue that in some cases the state will have good reason to prevent people from accessing disability screening technologies. This is because some disabilities contribute to valuable forms of human diversity which benefit our populations as a whole. In Chapter 4, I turn my attention to debates regarding cognitive enhancement. I argue that to date the focus of cognitive enhancement has been too narrow. Rather than considering enhancing just the cognitive attributes of individuals we should instead focus on enhancing our collective capacity to solve problems. I suggest this involves enhancing our ability to cooperate with each other as much as it involves changing aspects of our cognition. In my final chapter I discuss life extension technologies. I suggest that radically extending the lifespan of individuals may reduce the adaptability of our populations, and species as a whole, through both genetic and cultural mechanisms. I conclude by arguing for the need to think of human enhancement as a collective enterprise. When individuals use enhancement technologies to alter their traits, they do so in the context of many others having access to the same technologies. In order to secure the greatest benefit for all we need to coordinate our enhancement decisions.



human, enhancement, moral, philosophical, bioethics, cognitive, life extension, technologies, genetic, reproductive




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