Apprentice Adept

Apprentice Adept is a heptalogy of fantasy and science fiction novels written by English American author Piers Anthony. The series takes place on Phaze and Proton, two worlds occupying the same space in two different dimensional planes. Phaze is a lush planet of magic, where Proton is a barren mining planet of science. As the series opens, each person born on Phaze and Proton has an alternate self living on the other world. But if a person on either world lacks a duplicate (for instance if a Proton citizen immigrated there from another planet, or a counterpart from the opposite frame died), he can cross to the other through an energy "curtain" that circumscribes each frame.

The first three books in the series follow Proton serf Stile as he enters Phaze and becomes an important political force there. The next three concern the adventures of Mach (Citizen Blue's son), Bane (Stile's son), and Bane's companions. Finally, volume 7, Phaze Doubt follows Bane's and Mach's nine-year-old children, Flach and Nepe, among others.

In the series, Proton is only one planet in a galaxy of human-inhabited worlds. Most of the atmosphere of the planet has been destroyed through the mining of Protonite, a valuable energy source, and the inhabitants of Proton live in domed cities with artificial life support.

Despite its advanced science, Proton's socioeconomic scheme somewhat resembles the medieval period. The planet is run by fabulously wealthy Citizens but the bulk of the inhabitants are serfs. Serfs must be employed by a Citizen and remain naked at all times unless ordered otherwise by a Citizen. A Citizen has complete authority of his serfs and may order them to do anything he desires. The weakest among them have wealth to rival medieval kings. Serfs, however, are not slaves; the serfs of Proton have all chosen serfdom as their occupation (or are descended from those who have). After twenty years of work, a serf earns a gram of Protonite, and his retirement. While a paltry sum on Proton itself, this is enough to make the former serf comfortably wealthy elsewhere in the galaxy. Even then many serfs would choose to stay on Proton after their twenty years are up, but it is not permitted in most circumstances. The exception to this rule is getting far enough in the tourney (see below).

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