Abstract

Alchemical writings of Arabic origin introduced into the Latin natural philosophy of the twelfth century a cosmological issue that was at variance with Aristotelian cosmology: the idea of a subtle substance that stood at the origin of the four elements and encompassed heaven and earth. In this article, I consider the links of this notion with Hermetic and Stoic thought; its association with the technical process of distillation; its emergence in some philosophical texts of the early thirteenth century; and finally its full development in two fourteenth century alchemical treatises, the Testamentum attributed to Raimond Lull and the Liber de consideratione quintae essentiae written by John of Rupescissa