In Psion, Vinge uses Cat, the protagonist, to show the personal and sociological destruction caused by prejudice.

Cat is hated and mistreated because he is a mixture of Terran and Hydran.

Unfortunately for Cat, he has inherited from his Hydran mother distinctive eyes with elliptical pupils (hence his name) as well as telepathic powers.

Any "pure" Terran can tell instantly from his eyes that Cat has Hydran blood. Fearing the Hydran telepathic powers, Terrans shun Cat, or try to hurt him. In his short life Cat has been both physically and psychologically abused by those of "purer" blood. He has become a junkie, selling himself and the opportunity to abuse him to maintain his habit. Cat also has blocked out his ability to use his talent because it is the cause of his horrendous mistreatment.

Along with other outcasts, Cat lives in Oldcity, a slum literally...