  But are parental choices regarding non-disease traits simply morally permissible or are they morally obligatory? While advocates of liberal eugenics agree on the obligation to address disease-related genomic variants, they disagree regarding whether the use of reprogenetic technologies for non-disease traits is a matter of moral permissibility or obligation. For some proponents, it is morally permissible, but not obligatory, for parents to use (with some constraints) reprogenetic technologies to select or edit non-disease traits (Agar 2004; Green 2007). They reject the moral obligatoriness of these practices for several reasons. First, there is the difficulty of determining just what counts as an improvement (beyond addressing serious disease). For instance, Agar (2004) questions whether it is obviously better for a child to be highly intelligent (roughly approximated by a likely IQ of 160). Might some parents reasonably choose a more moderate level of intelligence for a child, presuming the child will have greater social opportunities in the latter case? Perhaps the overall freedom of the child of moderate intelligence will be greater than that of the child with high intelligence, even though on that one dimension the child’s capacities are comparatively lower. Second, while one might consider it reasonable to incur risks of reprogenetic intervention to treat or prevent diseases, it is by no means clear that the risk-benefit balance would be appropriate when dealing with non-medical traits.  Third, many recognize the importance and value of diversity (Green 2007). Given the many ways in which parents can attempt to improve the lives of their children, it is not clear why there would be a moral obligation to choose some non-disease traits over others rather than simply allowing parents to choose what they wish. Additionally, even if many people agree on the value of some non-disease characteristic and it becomes so common that its possession is practically required for equal participation in society, we might want to resist the temptation to make that intervention obligatory. For example, Agar (2004: 85) suggests this might happen with the trait “being somewhat happier than is now normal” if treatment tied to 5-HTTLPR, a genetic marker associated with upbeat temperament, became common. The now-typical temperament is not a disease, but a mere variety within the capacious normal range of functioning and would likely remain so even in a future society of 5-HTTLPR-enhanced people. A liberal eugenics cannot mandate any one view of the good life for its citizens.