Wikipedia contains spoilers
The Memory of Earth is the first novel
of the Homecoming saga of Orson Scott Card.
Humanity has lived for 40 million years in the
planet Harmony, after making Earth uninhabitable.
In order not to repeat the mistakes that led to
the destruction of civilization on Earth, a computer was left as guardian of this planet.
Its main mission was to prevent humans from
developing technologies that could make wars a
global affair. For that, humans were genetically
modified so they could communicate with the Oversoul, as the computer is known. However,
after this long time the Oversoul is beginning to
fail, and he choses a group of human to go to
Earth and update his programing.