What does engender or being engendered mean? Where do children come from? The new procreation methods reactivate the questions that have kept haunting humanity. Jean-François Peyret and Alain Prochiantz continue - with great humour - weaving the two imaginary worlds of theatre and science. Looking for a contemporary echo to the conflict which opposed Galileo to the Church, it is not on the ground of Astronomy that they find it but on the one of human reproduction technologies...