Too Long; Didn't Read
Psychohistory is an interdisciplinary science that combines sociology and mathematics with the goal to predict future events in large societies. The theory is inspired by the emergence of gas from billions of atoms, and similar amounts are considered when the first axiom talks about sufficiently large populations. The real world would face challenges related to three main areas - scale, limits of current knowledge, and ethics. We can't describe mechanisms underlying changes in societies mathematically with the required level of precision. We just don't understand them well enough. Yet.