When I was a student of Dalaran I was taught absolutes. The reigning theory at the time was that all things considered "magic" were through the Arcane, which was the primary source of all magical feats. If a Mage conjured a ball of fire, that fire was brought forth through Arcane energies. If a Priest healed, the man of the cloth was calling the Light through an Arcane pathway. If a tree grew, the plant was feeding from Arcane sources. As you can see, my education at the time was rather limited.