Why historians go around in circles

While scientists move steadily forward

History is not like science. Science moves forward as scientists accumulate knowledge about the physical world. Scientists today investigate different questions than scientists a generation or a century ago did. They often refine and occasionally revise old theories, but they rarely circle clear back to earlier starting points. In nearly all fields of science, progress is the norm and the expectation.

Not so in history. Historians constantly revive old debates, often in their original terms. How revolutionary was the American Revolution? The question was posed while the revolution was under way, and it provokes debate today. Is history driven by ideas or by material forces? Plutarch weighed in, and so did Marx, and so do contemporary historians.

New sources shed new light on the old debates, but they never settle the old questions. Politics sometimes renders previously acceptable arguments untenable, but those arguments don't go away; they merely go quiet. Was the Civil War about slavery or states' rights? In the 1920s it was perfectly acceptable to answer states' rights. Today the only permissible response is slavery. 

The correct answer is both. The secession ordinances of the Confederate states make plain that concern for the future of slavery loomed large in their decision to bolt the Union. Yet Lincoln's speeches, proclamations and letters show undeniably that his resistance to secession was grounded in his reading of the Constitution on states' rights—namely that these rights did not include the right of secession. He later added emancipation as a war aim, but he justified it in terms of its contribution to saving the Union.

The striking thing about the shift in views on this subject is that it has nothing to do with new evidence. It follows entirely from a reassessment of old evidence in the light of new necessities. 

Imagine if science worked that way. Suppose the second law of thermodynamics became politically inconvenient and a legislature somewhere outlawed increases in entropy. Besides making a laughingstock of that legislature, the law would fall dead from the law books as the universe paid it no attention.

Which is not to say scientists can ignore willful ignoramuses. Galileo was hounded by the Inquisition; teachers of evolution have been fired and fined. Today, climate science is rejected by modern flat-earthers who keep governments from passing laws to reduce emissions of greenhouse gases.

Yet there exists an objective world that ultimately has the last word in such matters. The planets really do move around the sun; new variants of covid evolve before our eyes; the glaciers and icecaps recede.

History affords no such reality checks. Leaving aside blatantly anti-factual arguments like the claim that the Democrats stole the 2020 presidential election, the big historical debates are not about facts but about the meanings of the facts. And the meanings involve basic questions of human nature. Who are we? Where did we come from? What do we owe to one another? Are we capable of improvement or irreparably fallen?

These questions lie in the realm of philosophy and religion as much as in that of history. It's no coincidence that philosophy and religion are as unable to make definitive progress as history. At least since Plato, philosophers have been asking and re-asking the same questions about human existence. Since long before Moses, priests and prophets have been asserting the existence of God or gods but been unable to prove it. 

What's the secret of science's success, compared with history, philosophy and religion?

It's simple. Science confines itself to answerable questions. For a theory to be scientific, it has to be falsifiable. Einstein improved on Newton by correctly predicting the apparent transit of Venus across the surface of the sun to a greater degree of precision. If Einstein's prediction had been wrong, his theory would have been rejected.

In this vein, scientists don't ask why, merely what. Why does the universe exist? The scientists leave that to the theologians, limiting themselves to describing—sometimes with excruciating precision—what the properties of the universe are.

Historians, by contrast, obsess over why. Why did European economies industrialize sooner than those of other continents? Why did Truman drop atom bombs on Japan? Why did the Soviet Union implode? 

Why questions are inherently unfalsifiable. We can't get inside the heads of historical figures, let alone the heads of whole nations.

Someday science may provide help on the why questions. Humans are made up of atoms, which obey the laws of physics; with enough data about those atoms, scientists may one day be able to explain and even predict human actions.

But maybe not. Measurement uncertainties and quantum effects may forever cast a veil over such detailed knowledge.

Which could be a good thing for historians. The most durable histories have always been those that subordinate analysis to description. Fashions in analysis—in explaining why—come and go. Careful description—one might say scientific description—can last a long time.