During the second half of the 19th century, the issue of the origins of the heavenly bodies took on increasing cultural importance, in both artistic and scientific circles. This paper, in focusing on the authors of scientific cosmogonies, shows the particular status of this theme in the context of a rapid institutionalisation of the sciences and in particular of astronomy. During the last decades of the century the boundaries between the heart and the margins of the scientific world, between amateurs and professionals, became increasingly hermetic, and at the same time the distribution of authoritative knowledge more and more difficult to challenge. We will try to show that the speculations on the origins of the cosmos are accompanied, for a wide variety of researchers at the margins of the astronomical institutions, by a genuine hope for scientific recognition, and represent a form of resistance to the establishment of the strongly hierarchical and elitist structures of astronomy in France.