Why psychology and history don’t have overarching theories — and probably never will

Figs in Winter
Science and Philosophy
9 min readJul 31, 2020


The cover of Isaac Asimov’s Foundation novel

Physics has two dominant paradigms: quantum mechanics and general relativity. And physicists are actively attempting to merge the two into a unified theory of fundamental reality. Biology has one unifying theory: the so-called Extended Synthesis that built on the original Darwinian insight of the middle 19th century. Chemistry has its own unified theory: it basically boils down to physics.

But when we move from the natural to the social sciences, like psychology, or the humanities, like history, we don’t find anything analogous. Why?

Sure, there have been attempts in that direction. In psychology, several overarching theories have been proposed, and eventually abandoned: Freudianism and behaviorism, to mention the big ones. In history, people used to subscribe to something akin to what is now derisively referred to as “The Great Men” theory, where things happen because a great man — Julius Caesar, Napoleon, what have you — single-handedly redirects the course of events. At the opposite extreme, we have Marxist theories of history, where great men don’t count for nothing, and it all comes down to economics and the class struggle. None of that has worked out too well.

Of course, there are currently ongoing attempts at a unified theory, in both fields. In psychology, some people push what is referred to as an evolutionary psychological key to understand human behavior. The basic concept is sound: human beings are animals, and animal behavior evolves by natural selection. So, the argument goes, the human behavioral repertoire is also the result of natural selection.

Except that things aren’t so simple when it comes to human beings. There are two issues that frustrate the efforts of evolutionary psychologists: the near-impossibility of testing their theories, and cultural evolution.

Evolutionary biologists have devised three major strategies to test hypotheses concerning the evolution of a given trait: (i) comparative phylogenetic approaches; (ii) an examination of the fossil record; and (iii) direct quantitative studies of natural selection in the field.

They all fail abysmally when it comes to evolutionary psychology, simply because the human species is a bad…