New eugenics is distinguished from previous versions of eugenics by its emphasis on informed parental choice rather than coercive governmental control. Eugenics is sometimes broken into the categories of positive eugenics and negative eugenics. Another distinction is between coercive eugenics and non-coercive eugenics. According to Edwin Black, many positive eugenic programs were advocated and pursued during the early 20th century, but the negative programs were responsible for the compulsory sterilization of hundreds of thousands of persons in many countries, and were contained in much of the rhetoric of Nazi eugenic policies of racial hygiene and genocide. New eugenics belongs to the positive eugenics category. Bioethicists generally consider coercive eugenics more difficult to justify than non-coercive eugenics, though coercive laws forbidding cousin marriage, for example, are widely considered justified. Compulsory sterilization of those deemed unfit is a form of coercive eugenics that has been overwhelmingly rejected, and is illegal under many national and international laws.
New eugenics practices
New eugenics generally supports genetic modification or genetic selection of individuals for traits that are likely to improve human welfare. The underlying idea is to improve the genetic basis of future generations and reduce incidence of genetic diseases and other undesirable traits. Some of the practices included in new eugenics are: pre-implantation diagnosis and embryo selection, selective breeding, and human enhancement through the use of genetic technologies, such as embryo engineering or gene therapy.
Ethics
New eugenics was founded under the liberal ethical values of pluralism, which advocates for the respect of personal autonomy, and egalitarianism, which represents the idea of equality for all people. Arguments used in favor of new eugenics include that it is in the best interest of society that life succeeds rather than fail, and that it is acceptable to ensure that progeny has a chance of achieving this success. Ethical arguments against new eugenics include the claim that creating designer babies is not in the best interest of society as it might create a breach between genetically modified individuals and natural individuals. Additionally, some of these technologies might be economically restrictive further increasing the socio-economical gap. Dov Fox, a law professor at the University of San Diego, argues that new eugenics cannot be justified on the basis of the underlying liberal theory which inspires its name. He argues that heritable mental and physical capacities that are generally valued can be considered as alternative to John Rawls's social primary goods. In this case, natural primary goods. Fox suggests that reprogenetic technologies like embryo selection, cellular surgery, and human genetic engineering, which aim to enhance general purpose traits in offspring are practices a liberal government leaves to the discretion of parents than like practices the state makes compulsory. Fox argues that if the liberal commitment to autonomy is important enough for the state to mandate childrearing practices such as health care and basic education, that very same interest is important enough for the state to mandate safe, effective, and functionally integrated genetic practices that act on analogous all-purpose traits such as resistance to disease and general cognitive functioning. He concludes that the liberal case for compulsory eugenics is a reductio ad absurdum against liberal theory. The United NationsInternational Bioethics Committee wrote that new eugenics should not be confused with the ethical problems of the 20th century eugenics movements. Regardless, they have stated that it is still problematic as it challenges the idea of human equality and opens up new ways of discrimination and stigmatization against those who do not want or cannot afford the enhancements.