HERMETISM designates the pagan corpus (written for the most part in the region of Alexandria) of the so-called Hermetica, which contains the pagan writings called Corpus Hermeticum (second and third centuries CE) attributed to the legendary figure Hermes Trismegistos (also Trismegistus), otherwise called Mercurius. Neo-Alexandrian Hermetism (henceforth often referred to as Hermetism also) designates the various philosophically and/or esoterically oriented adaptations and commentaries which that corpus has given rise to, particularly in the modern period (i.e., from the Renaissance up to the present time). Neo-Alexandrian Hermetism constitutes one of the modern esoteric currents and is the subject of most of this article. The term Hermeticism, which is more vague, frequently has been used as a synonym for esotericism and alchemy.

The Corpus Hermeticum had a strange destiny. In the Middle Ages, besides the Asclepius, only a few rare extracts were known, and yet their supposed author...