Alchemy

Alchemy is a two-headed beast, both physical and metaphysical. Its practioners run the gamut from genuine mystics to natural philosophers to outright frauds. Its study is in serious decline in Theah, as the new science of chemistry takes its place.

Physical Premise of Alchemy

Alchemists believe in a unity to the world. All metals, for example, are manifestations of an Ideal Metal, more or less perfectly realized. Gold comes closest to the Ideal Metal, since it does not tarnish, is not changed by fire, and is immune to the action of corrosive liquids. Silver is next-closest, and so on, until one gets to the basest metal of all, lead.

All metals, it is thought, are "growing" toward gold, just as plants grow from seedlings to trees. Alchemy hoped to discover this growth process and speed it along. State transformations were key here, as the "impurities" that kept the baser metals from achieving the Ideal Metallic state would be removed. A sample of this Ideal Metal (which is usually called the Philospher's Stone) would be a catalyst to change more metals into gold. Its miraculous purity would mystically transfer to other metals, bringing them up to its level.

Many people were just interested in getting lots of gold, cheap. Some hoped to find it via alchemy; some pretended to practice alchemy to get "research funding" from hopeful noblemen. Others were hoping to prove their philosophy of a universal unity; if transformations could be performed, it would support their ideas.

Metaphysical Premise of Alchemy

The idea of transforming a "base metal" into an Ideal Metal by removing its impurities and revealing its essential oneness with the Ideal was also applied to the human spirit. If all humans are creations of divine Theus, they somehow share in his divine nature. This nature is obscured by impurities of spirit - sins. As impurities are removed, more of the Ideal Human is revealed.

Exactly how one should go about removing these impurities was a little fuzzy. The alchemists thought they were on to some deep and secret knowledge, so clearly the workaday rules and doctrines of the Vaticine Church weren't the proper crucible to effect this transformation toward the Ideal. Most considered the practice of physical alchemy to be the proper method to achieve personal transformation. The physical alchemy was an allegory for the spiritual alchemy, and by repeatedly practicing the one, the alchemist hoped for enlightenment about the other.

Further Reading

Wikipedia article on alchemy.