What is Psychohistory?
Psychohistory is the cornerstone of Isaac Asimov's Foundation series. It is a theoretical branch of mathematics that deals with the reactions of human conglomerates to fixed social and economic stimuli. The discipline draws from several real-world sciences:
- Statistics: To analyze large-scale data patterns
- Sociology: To understand group behavior
- History: To identify repeating patterns in civilization
- Mathematics: To create predictive models
Core Principles
The Population Requirement
Psychohistory only works on sufficiently large populations. The population must be in the billions for predictions to be accurate. Individual behavior remains unpredictable, but mass behavior follows statistical laws.
Statistical Certainty
Like the kinetic theory of gases, psychohistory cannot predict individual actions but can determine overall trends with mathematical precision. The larger the sample, the more accurate the prediction.
The Ignorance Requirement
The population being predicted must remain unaware of the predictions. If people know what psychohistory predicts, they might alter their behavior, invalidating the predictions. This is why the Seldon Plan remained largely secret.
Development and History
Hari Seldon began developing psychohistory early in his career as a mathematician on Trantor. Initially, it was purely theoretical—a mathematical curiosity. However, as he refined the equations, Seldon realized psychohistory could be applied practically to predict the fall of the Galactic Empire and the subsequent dark age.
"Psychohistory dealt not with man, but with man-masses. It was the science of mobs; mobs in their billions."
The Seldon Plan
Using psychohistory, Seldon predicted that the Galactic Empire would fall within 500 years, followed by 30,000 years of barbarism before a Second Empire could arise. However, he also calculated that by taking specific actions, this interregnum could be reduced to just 1,000 years.
The result was the Seldon Plan: a detailed roadmap spanning a millennium, designed to guide humanity through the dark ages via two Foundations—one dedicated to physical science, the other to mental science and psychohistory itself.
Limitations and Vulnerabilities
Despite its power, psychohistory has significant limitations:
- Cannot predict individual actions: The appearance of exceptional individuals (like the Mule) can threaten the entire plan.
- Requires ignorance: If the population learns the predictions, their behavior changes, invalidating them.
- Statistical limits: Even with large populations, there's always a margin of error.
- Complexity: The mathematics is so complex that only a handful of people can truly understand and use it.
Psychohistory vs. Real Science
While psychohistory is fictional, it draws inspiration from real scientific disciplines. Modern computational social science, big data analytics, and complexity theory share some conceptual similarities with Asimov's vision, though nothing approaching psychohistory's predictive power exists in reality.
Economists and sociologists use mathematical models to predict trends, but human behavior remains far more unpredictable than psychohistory suggests. Asimov himself acknowledged that psychohistory was a literary device rather than a realistic scientific prediction.