Often described as “anti-meliorists” or “bioluddites,” thinkers associated to “bioconservatism” have developed in the early twenty-first century a vigorous criticism of technoscientific and biomedical advances which aim to enhance human capacities. This article offers a critical reading of the conservative bioethics through the examination of the thought of two of its major thinkers, the philosopher Leon Kass and the political scientist Francis Fukuyama. If these thinkers have the merit of recalling the need to consider the living anchor irreducible of human beings in the era of bioeconomy and the increasing exploitation of the living world, however, we will see that the dogmatic conception of “human nature” that supports their argument does not offer an appropriate framework to confront the ethical and political issues posed by the current desire for enhancing human performances.