||Harris 1992 argues that it is mandatory to modify disabilities through gene-therapy, including many traits that are considered normal or non pathological. Savulescu 2001 argues that parents have a moral obligation to select the best children in the context of pre-implantation genetic diagnosis (PGD) based on available genetic information. Agar 2004 endorses the liberal version of eugenics, since, unlike early twentieth century eugenics, it is compatible with a pluralism of different conceptions about human flourishing. Against such or similar views, Habermas 2003 defends a principled distinction between gene-therapy to cure disease and genetic manipulation allowing parents to select the traits of future children. The latter is seen as incompatible with egalitarian relationships between human beings and their freedom of choice. Taking an intermediate position, Buchanan et al 2000 defend a Rawlsian approach to genetic justice, inspired by Buchanan's idea of a genetic decent minimum (Buchanan 1995) and Daniels' normal functioning approach to health care (Daniels 1985). They hold that society has the duty, as a matter of justice, to use gene therapy to correct disease, subject to reasonable resource constrains. In addition to this, in a future society in which genetic enhancements are widespread, normal functioning may require enhanced human capacities. They also attempts to reject the "social model of disability", in an extreme form, while recognising that the classification of X as a disability is, today and in a genetically modified future, society-relative (Silvers 2001).