Currently Professor Emeritus at University of Paris I Panthéon-Sorbonne, he is also the founder of the Centre for the Study of Techniques, Knowledge and Practices (CETCOPRA) and the “Techniques, Environment and Societies” option in the Masters in Philosophy and Society. Alain Gras is a techno socio-anthropologist and has lived in or participated in in-depth research in various countries, particularly in Sweden, Ghana, Brazil, Morocco and Spain. He has done a great deal of work on the problems caused by the introduction of advanced technology in aeronautics and subsequently became interested in the energy problem. This issue is treated as a historical problem: the thermo-industrial society, that is, one founded on the use of fire to the detriment of other elements, one imposed and not in continuity with a technical evolution but in rupture with it. It is worth asking the question “why” and not “how”, which is what classical historians ask, because it is the fire technology that has made our current expansion path possible: the expansion of capitalism that has now gone wild, the creation of a mega machine made of technical macro-systems, as well as our obsession with speed, outsourcing and the all powerful, which has now become the headlong technological rush. Selection of related works: Grandeur et dépendance. Sociologie des macro-systèmes techniques, PUF, 1996 Fragilité de la puissance. Se libérer de l'emprise technologique, Fayard, 2004 Le choix du feu. Aux origines de la crise climatique, Fayard, 2008(Editor) L'avion : le rêve, la puissance et le doute, PU Sorbonne, 2010.