Counterfactual archaeology and preservation bias: what traces a proposed civilization should leave, which could survive, and what would change the conclusion.
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We are not asking you to believe lost-civilization claims, and we are not here to laugh at them either.
Instead we ask a more useful question: if a claim were true, what evidence should it have left behind?
Then we ask what nature and people could have erased or moved — erosion, flooding, glaciation, corrosion, reuse, excavation, museums, war.
Then we ask what evidence actually survives today, and what natural or ordinary explanation could produce the same thing.
Finally we ask the question that keeps this honest: what finding would change the conclusion? Missing evidence is not proof, but it is not equally meaningful in every circumstance.
Five plain-language steps you can apply to any claim in this category — or to one you brought with you. Each topic page works through them, and the full ten-question research version sits inside the framework entry.
Step 1
State it precisely enough that some possible finding could contradict it. “Something strange happened long ago” cannot be tested.
Step 2
Physical, geological, chemical, biological, linguistic or cultural traces. This is the step most claims skip.
Step 3
Ceramics and mine voids last; timber, textiles and documents do not. Erosion, burial, sea-level change, reuse and excavation all move or destroy evidence.
Step 4
Real objects, sites, datasets and publications a reader can check — not assertions about missing artefacts.
Step 5
Name the discovery that would strengthen, weaken or falsify the claim. If nothing could, the claim has left the evidence conversation.
An underwater lake sounds like a contradiction until we distinguish water by its properties. In a brine pool, very salty water is denser than the seawater above it, allowing a distinct…
Read full entryA granite block has been granite for hundreds of millions of years. Cutting, dressing and setting it changes nothing about the rock's age.
Read full entryThis is a thought experiment, not a prediction and not a claim about the past. Suppose modern industrial civilization ended today — no maintenance, no pumping, no repair, no one left to…
Read full entryIn 2018 Gavin Schmidt, a climate modeller who directs NASA's Goddard Institute for Space Studies, and Adam Frank, an astrophysicist at the University of Rochester, published a paper in the…
Read full entryThis is an explicit Arcanum thought experiment. It is a demonstration of how context loss manufactures false conclusions.
Read full entryThe question is narrow and answerable: can an oral tradition carry accurate information about a real physical event across many generations, while the explanation attached to that…
Read full entryEvery account of a lost civilization contains a hidden assumption about transmission: that what a society knew is roughly what its descendants would inherit.
Read full entryMany cultures record traditions of earlier worlds or ages that ended. Modern alternative-history writing tends to gather these into a single implied claim: that humanity remembers a prior…
Read full entry"Advanced civilization" is usually read as "like us, earlier." That reading smuggles in a whole developmental sequence — coal, iron and steel, steam, electricity, electronics, plastics,…
Read full entryThis entry does not assert that giant humans existed, and it does not assert that the question is closed by ridicule.
Read full entryThis is the method the rest of the category applies. It is deliberately reusable: the same ten questions work on Atlantis, on ancient aviation, on acoustic levitation, on floating cities,…
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Practices at the edge of accepted medicine — what has been studied, what has not, and where the record ends.
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Techniques and instruments that were once in use and later abandoned, misplaced or superseded.
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Suppressed records, contested chronologies and the politics of what gets written down.
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Cosmologies, rites and symbol systems recorded across the ancient world.
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