Alchemy in Europe and the Middle East

Such practical alchemical work received theoretical justification in part from Greek natural philosophy. Although Aristotle (384–322 B.C.E) did not write about alchemy per se, he provided a theory of matter that made it possible to conceptualize the transmutation of metals. Aristotle posited the notion that all things were composed of the same formless, passive matter (materia prima), which was then transformed into a specific substance by an active, shaping form. For alchemical theory, Aristotle's crucial notion was that, because the four elements—earth, fire, water, and air—were composed of the same basic matter, they could be transmuted into one another by altering their forms. Through the application of heat, for example, water could be transmuted into "air" (steam). From this, alchemists developed the idea of isolating the materia prima in metals and transmuting one into another through the use of an agent known as the philosophers' stone or elixir.

The rich cultural resources of the Hellenistic world further developed alchemy's theoretical foundations. From Stoic matter theory, pneuma, or spirits, replaced Aristotelian forms as the active defining force of matter. From Babylonian astrological traditions alchemists adopted the identification of the seven metals (gold, silver, mercury, copper, iron, tin, and lead) with the seven planets (sun, moon, Mercury, Venus, Mars, Jupiter, and Saturn) and the division of both metals and planets into male and female. Finally, the central transmutational process of reducing metals to their materia prima before recreating them as gold or silver drew on ideas presented in the Egyptian myth of Isis and Osiris, in which Osiris was killed and dismembered before Isis brought him back to life.

A collection of texts written in the first centuries C.E. known as the Hermetica were attributed to Hermes Trismegistos, a figure identified with the Egyptian god Thoth, the mythical creator of the arts and sciences. Although alchemy was only one topic among many in the Hermetica, in the European Middle Ages Hermes came to be known as the legendary first alchemist and alchemy as the "hermetic art." The Hermetica ranged in content from medical, astrological, and magical treatises to much more theosophical ruminations on the redemption of the spirit through gnosis.

This association in the Hermetica between practical alchemy and spiritual gnosis found its way into alchemical theory through later authors. The link between spiritual and practical goals of transmutational alchemy is particularly evident in the work of the Alexandrian Zosimos of Panopolis (fl. 300 C.E.; later Latinized as Rosinius). In his compilation of older alchemical writings known as the Cheirokmeta, Zosimos wove his practical alchemy into a mystical theoretical framework that would prove just as enduring as alchemy's more technical concerns. Full of secretive language, dream sequences, and allegories, Zosimos's texts describe alchemical processes metaphorically—as sexual generation, for instance—and highlight the role of spirits in transforming matter. With a clear debt to Gnosticism, Zosimos established an enduring connection between practical laboratory work and spiritual perfection.