Les manipulations génétiques appliquées à l'homme : ce que nous apprend le mythe d'Er de Platon

The debates on the revision of the laws of bioethics highlight the reserves, founded or not, of the public with respect to the genetic engineering applied to the embryo. For better understanding the stakes of this research and these technologies, we put in parallel the current situation with the myth of Er in Plato's Republic. This text shows us the dangers of the integral control of the beginnings of life, and in particular the threat that such a control makes weigh on the idea of human nature. Because the choice, by the parents, of their children's phenotypical characters (what is called liberal eugenics) could lock up the new ones in a constraining biological destiny, opposite with the freedom which is the characteristic of human. Freedom needs an opened, not predestined, future. The liberal eugenics accredits the idea that human beings can be programmed before their birth like manufactured goods, according to a schedule of conditions defined by the parents or the society. It carries out a seizure on the future which must be condemned. Not only it is not with the service of the future generations, whose most invaluable good is not perfect health but freedom; but it tries to control them in the name of their own happiness. Prudence is thus of setting, and justifies the maintenance of a great vigilance of the citizens vis-a-vis work of the laboratories, vigilance whose framework can be only legal.