By reading the cycle, I very much liked Paolini's conception of magic, illustrated in the scene where Eragon was told to get the power for lifting the stone out of his surrounding and has been shocked by feeling how one ant after another dies.
The lesson to be learned was that magic is "fueled" by the energy of life itself and this resource can be exhausted which leads to death. So basically, the superhumanity is bounded to a material source and compatible with a concept of continuity of energy, i.e. basic physical conceptions. A difference e.g. from Star Wars' Force, as I understand it.
Are there other books/works/authors that promote similar conceptions?