Abstract
For the prominent figures of dystopic posthumanism biotechnological progress means not only new possibilities of solving the most nagging problems, but also many extremely dangerous consequences: a modification of social organization, an undermining of morality, and some changes in the way we understand our identity. Thinkers such as Fukuyama, Kass, Sandel and Habermas consider those consequences as a threat to human nature. In the article I examine the way they construct the latter notion (i.e. human nature) in their arguments.