 Several critics of genetic enhancement argue that permitting enhancement is liable to undermine important human values. Sandel argues that the control that enhancement technology would allow parents is liable to undermine their humility in the face of the gift of their children, impose responsibilities that we are not prepared to deal with, and threaten social solidarity (Sandel 2007). Habermas argues that parents who genetically enhance their children will, through the control they exert, prevent their children from entering relationships of moral equality and undermine their ability to be autonomous (Habermas 2003). Both have been criticized for exaggerating the likely effects of permitting enhancement technologies (Fenton 2006; Lev 2011).