The Art of Memory is first found in existing ancient documents as a set of memory tools for rhetoric and oration. It is mentioned by Aristotle, Cicero and Quintilian, among others. Early Christian monks, who generally had some familiarity with the classical tradition, transformed the Art of Memory into a way of remembering and meditating upon sacred texts, Psalms, prayers and the writings of the early Church fathers.
With the rediscovery of Aristotle during the later Medieval period, the practice of the Art of Memory was reinvigorated. Thomas Aquinas was a proponent, claiming that the Art of Memory was useful for meditation upon the virtues and to examine one's own spiritual state.
The weird groovy part of all this comes during the Renaissance with folks like Giordano Bruno and Ramon Llull, who took the Art of Memory, Christian mysticism, occultism (mainly the Hermetic tradition), and some emerging scientific thoughts and mashed it all together. To quote Wikipedia (the universal authority on everything): According to one influential interpretation [of Ramon Llull], his memory system was intended to fill the mind of the practitioner with images representing all knowledge of the world, and was to be used, in a magical sense, as an avenue to reach the intelligible world beyond appearances, and thus enable one to powerfully influence events in the real world.
See any similarity between the Art of Memory and the Vancian magic system? The Art of Magic has given me something to hang my hat on in terms of a gaming concept without having to monkey in anyway with game system mechanics. At the same time, I never really felt like I needed to have an explanation for how the D&D spell system worked. I learned it back in the 70s with Dr. Holmes and it works for me. I am also fine with how FATE (e.g. Dresden RPG) and GURPS each approach magic. I am too much of a gaming pragmatist, so I only worry about whether it works "in game" or not. I find the Art of Memory mainly interesting as a student of history, not as a gamer. Even so, I thought the similarity to Vancian magic was very cool.
Note: The accompanying image contains three "memory seals" of Giodano Bruno (source: Wikipedia)