You've probably encountered someone passionately explaining how everything you learned in school is wrong. The moon landing was faked. Shakespeare didn't write his plays. Ancient aliens built the pyramids. These claims often come wrapped in impressive-sounding evidence and urgent warnings about suppressed truth. So how do you tell the difference between a genuine historical revision—which happens all the time—and a conspiracy theory dressed up as scholarship?

Here's the thing: historians love overturning established narratives. There's no faster path to academic fame than proving everyone wrong about something important. But there's a method to this madness, a set of tools professionals use to separate legitimate revisionism from wishful thinking. Let's peek inside the historian's toolkit and learn how to evaluate extraordinary claims ourselves.

Historians operate on a simple principle: extraordinary claims require extraordinary evidence. If you're arguing that a battle happened on Tuesday instead of Wednesday, you need decent evidence. If you're arguing that an entire civilization has been erased from history, you need overwhelming, independently verifiable proof from multiple unrelated sources.

Think of established historical narratives like buildings. Each brick represents a piece of evidence—documents, archaeological finds, contemporary accounts, physical artifacts. A well-established narrative has thousands of interlocking bricks, placed there by generations of researchers checking each other's work. Conspiracy theories often ask us to demolish the whole building based on a few cracks in the mortar. Sometimes cracks do indicate structural problems. But more often, they're just cracks.

The key question isn't could this alternative explanation be true—almost anything could be true. The question is: does this new claim explain the existing evidence better than the current explanation? Does it account for all the evidence, or does it cherry-pick convenient bits while ignoring inconvenient ones? Legitimate revisions typically explain anomalies that the old interpretation struggled with. Conspiracy theories typically create more anomalies than they solve.

Takeaway

When evaluating a historical claim, ask yourself: does this explanation fit all the available evidence, or only the pieces someone has selected for me? The more evidence a theory has to dismiss or explain away, the weaker it probably is.

William of Occam, a medieval philosopher, gave us a handy principle: when you have competing explanations, the one requiring fewer assumptions is usually correct. This isn't because the universe is simple—it isn't—but because every additional assumption is an additional opportunity to be wrong.

Consider two explanations for why historical records seem incomplete. Explanation A: record-keeping in pre-modern societies was inconsistent, documents decay, wars destroy archives, and much of human life simply wasn't considered worth recording. Explanation B: a secret organization spanning centuries has systematically located and destroyed specific documents while planting fake ones, bribing or intimidating thousands of archivists, librarians, and scholars across dozens of countries, all without leaving evidence of their existence. Both are technically possible. But Explanation B requires us to assume the existence of an organization with capabilities that would make most governments jealous.

The beauty of Occam's Razor is that it doesn't demand certainty. It just asks: which explanation requires me to accept more unproven things? Historians are perfectly comfortable with uncertainty and incomplete knowledge. Conspiracy theorists often aren't—they need an explanation for everything, which paradoxically leads them to explanations that explain nothing reliably.

Takeaway

Before accepting a complex explanation involving hidden actors and suppressed truths, ask: is there a simpler explanation that fits the facts just as well? Boring explanations are often correct precisely because they're boring.

Here's where historians really earn their keep. Source criticism means systematically asking: where does this information actually come from? Who created this document and why? What biases might they have had? Can this be verified independently? It's detective work, and it's surprisingly fun once you get the hang of it.

Conspiracy theories often fail the source test spectacularly. Follow the citation trail backward and you'll frequently find it loops back to a single dubious source, or to sources that don't actually say what they're claimed to say, or to no source at all—just confident assertion. Professional historians, by contrast, build arguments from multiple independent sources that corroborate each other. When they quote a document, you can go read it yourself and verify their interpretation.

Another red flag is what historians call anachronism—attributing modern concepts or capabilities to past people and institutions. Ancient civilizations were brilliant, but they had different knowledge, technologies, and worldviews than we do. Claims that require past actors to have capabilities they couldn't possibly have possessed—or to care about things they had no reason to care about—should trigger immediate skepticism.

Takeaway

Always ask: can I trace this claim back to its original source? If the citation trail is circular, missing, or leads to sources that don't support the claim, you've likely found the point where history ends and invention begins.

The goal isn't to become cynical about historical claims—it's to become appropriately skeptical. Historians revise our understanding of the past constantly; that's literally the job. But there's a difference between revision based on new evidence carefully evaluated and theories that require dismissing everything we know.

Next time you encounter a startling historical claim, run it through these tests. Check the evidence standards, apply Occam's Razor, and follow the sources backward. You don't need a PhD to think like a historian. You just need patience, curiosity, and a healthy respect for how hard it is to actually keep secrets.