It becomes apparent how tightly knit is the network of necessities that, in the sixteenth century, links together all the elements of knowledge: how the cosmology of signs provides a duplication, and finally a foundation, for reﬂection upon prices and money; how it also authorizes theoretical and practical speculation upon metals; how it provides a communicating link between the promises of desire and those of knowledge, in the same way as the metals and the stars communicate with one another and are drawn together by secret affinities.