re: @wolfkitty42

To be as brief as I can be, Hermeticism is a set of religious, philosophical and scientific beliefs from which we take most of our western understanding of alchemy and astrology. It is named after the legendary figure of Hermes Trismegistus, sort of a fusion between the Greek god Hermes and the Egyptian god Thoth, and would be highly influential throughout Ancient ages, Middle Ages and the Renaissance. The scientific part of it would eventually culminate in the field of chemistry, while the religious and philosophical parts would be used as a base for the modern esoteric/occultist movement.

The Tabula Smaragdina (Latin for "Emerald Tablet") we see in Ly'lac's room is a direct reference to the main text of Hermeticism, down to the use of the original phrasing of the famous Hermetic say "as above, so below". This is one of the many nods to both Hermeticism and Thelema, an esoteric religious movement founded by the professional weirdo Aleister Crowley which does take a lot from Trismegistus' attributed writings.

While I could spend hours yapping about specific concepts in Hermeticism (and if we keep doing the references in Beyond Canon, I just might), that would probably be a lot and quite inapproachable, so I'll end here for now.