<title> SUMMARY </title>Contemporary movements, united by their common rejection of traditional knowledge and by their common beginnings and development outside formal school boundaries, libertinism and the new science are often considered, evaluated and classified in the univocal light of modern thought introduced by Descartes. A comparison totally unfavourable to libertinism which did not benefit from the attempt made in some cases to assimilate it to the scientific revolution in the name of a common anti-dogmatic character. The movements were in fact distinct in their aims and motives and their occasional interaction must not make us forget the contemporary presence of different and often contrasting ideas at the dawn of modern thought. The aim of this paper is to overcome the historiographical approach which, by privileging a single access to modern thought, evaluates all the others according to the same measure.The paper, through an examination of the European discussion stimulated by Galileo's Sidereus nuncius, shows the philosophical consequences of the astronomical revolution and the series of projects, hopes and misunderstandings that marked its course. An event that did not encounter the indifference of libertines like Naude, who read in the celestial revolution confirmation of the crisis of terrestrial knowledge. In Italy the bond between libertine thought and the scientific revolution came tragically into being as from the condemnation of Galileo and found its consecration in the Neapolitan trial of the atheists at the end of the seventeenth century, thus reuniting in the name of a single orthodoxy, two different conceptions of nature and knowledge.