Sails & Sabres
There are two major theories widely accepted about the nature of Arcane Magic that have been around for a very long time. There is debate about which is the more likely at many levels of research. Bear in mind that the vast majority of people have really bizarre interpretations of what magic is and how it works, and that includes many novice magic users, too.
Dormant Ocean Theory: DOT posits that magic exists as an ambient energy from the formation of the multiverse, permeating it entirely, just outside of our ability to perceive it. This energy flows in variable currents which explain ley lines and why some areas seem to allow for more powerful arcana. This magic ocean does not normally react with anything, and the central action of spellcasting is to manipulate, or activate, the ambient energy in such a way as to manifest a desired change. This is done through sound, specific motions, and focus items that the arcanist can use as a sort of visual or conductive aid to properly direct his actions. Different materials, while not reacting with the dormant energy, do conduct activated magic or promote specific activity once introduced to activated magic, which accounts for the need for material components, particularly in complex or powerful spellcasting.
There are some researchers whose primary work is studying the flow of the dormant ocean or experimenting to discern different materials’ conduction or promotion properties.
Mana Theory: Mana theory is a more ascetic premise than DOT and has detractors among the most academic and “scientific” arcanists. Mana theory is similar to DOT in that it posits magic as a permeating energy, where it differs is the source. Mana theory is built on the idea that magical energy originates in living organisms, that it is produced by life. The more vibrant and flourishing that life, the more magical energy it can radiate. Ley lines are attributed to ancient rivers or routes of migration, or as a natural flow of magic between nexi of particularly powerful radiance.
The specific nature of magical energy arises from the source organism, so an apple tree produces slightly different energy than an orange tree, and both trees’ magic is far different than that produced by a good-hearted human man, which is in turn slightly different than magic produced by a dark-hearted human man.
The act of spellcasting is the manipulation of the caster’s own Mana, the energy radiating from him, and/or the manipulation of other creatures’ Mana. These two central methods are called Endoconversion and Exoconversion respectively, and have a wide variety of sub-types investigated by advanced scholars.
The major conflict between these two camps is the source of magical energy. Has it always been here or is it produced by living things? Does it reflect our natures or are we reflections of the magic around us? The deeper philosophical implications are a very active field of debate and contribute to the more academic one.
Wizards tend toward DOT, while sorcerors tend toward Mana Theory. Generally outside the debate, clerics are often split themselves. Mana theory is more in-line with the druidic traditions, and many other deities arisen from mortal races. Disciples of deities such as the Sunlord, Boccob, or Nerull, however, are more inclined toward DOT due the eternal and timeless nature of their ‘gods’ (or the eccentricities of praying to a being who became a deity in the pursuit of empirical research).