Isaac Asimov's 'Foundation' series is primarily based on the fictional science of 'Psychohistory', which predicts the future of:
- Individual human behavior
- Large populations and galactic empires using statistics
- Alien ecosystems
- Time travel paradoxes
Answer: Large populations and galactic empires using statistics
Hari Seldon invents Psychohistory to predict the fall of the Galactic Empire and shorten the ensuing dark ages, forming the core premise of Asimov's monumental series.