How does the magus change over the course of the novel, The Thief?

The magus begins the journey as a smug leader, but he becomes more open-minded and trusting as the story progresses. When the travelers leave Sounis, the group, led by the magus, insults Gen by calling him an idiot, a fool, a "useful sort of tool," and "O scum of the gutter." By the end of their travels however, the magus has gained respect for Gen, becomes concerned about his welfare, and finally comes to realize that Gen is really Eugenides, the Queen's Thief of Eddis.