 Such arguments have, however, been criticized on a number of grounds. Some suggest that parental obligations to their offspring cannot be so strong as to ground an obligation to select against disability (Williams 2017); others claim that “complex concepts such as the good life, the best life, and human flourishing, are not reducible to simple elements or constituent parts which might be identified by the testing of embryos [and selection of sperm donors]” (Parker 2007: 281); and others still question the link between disability and low levels of welfare (Barker &amp; Wilson, 2019) and/or claim that appealing to impersonal harms devalues those with disabilities by suggesting that their lives are worth less than those without disabilities (Asch 2003; Bennett 2009). Yet, while many authors suggest that there cannot be an obligation to select against disability, it is often held that prospective parents should still be at liberty to select against disability in their offspring on the basis of personal preferences.