If you want an explanation to magic, here's my 'theory':
There is a thing called Mana, which resides in every living thing, as well as the earth itself. Mana is something close to spiritual energy, and constantly radiated from living things. Some people can pick up on this, sensing other people they cannot see or hear, or detecting large amounts of it somewhere. Mana has the ability to be controlled, although it takes great knowledge and practice to accomplish such feats. It is something one must begin to learn from birth. Mana can be concentrated, dispersed, or used to fuel other practices. High concentrations of Mana can cause strange abnormalities, such as flames or lightning. Early man feared this, even in nature, and called it Magic. This concentration of Mana can also be controlled, although it required even more practice. This is how one performs feats that most call magic.