Foundation Series by Isaac Asimov

Foundation Series: A mathematician develops psychohistory, a way to predict the future of large populations, and creates a plan to save the Galactic Empire from collapse by establishing the Foundation — a group meant to preserve knowledge and shorten the coming dark age. The series follows their struggle to guide humanity’s future across centuries.

• Foundation
  A group of scientists creates a plan to preserve knowledge and shorten the fall of the Galactic Empire.
• Foundation and Empire
  The Foundation faces a powerful warlord and the mysterious threat of the Mule, a mutant conqueror.
• Second Foundation
  The search for the secretive Second Foundation, guardians of psychohistory, intensifies as they try to stop the Mule.
• Foundation's Edge
  A quest begins to find the hidden Second Foundation, revealing secrets that challenge the future of the galaxy.
• Foundation and Earth
  A journey to find Earth, the legendary origin of humanity, and unlock more cosmic mysteries.
• Prelude to Foundation
  The origins of psychohistory and its creator’s early struggles to develop the theory.
• Forward the Foundation
  The final years of the psychohistory pioneer, chronicling his personal and political battles to save the future