One Thousand and One Conjectures

Greenland's ice sheet and Roman monetary history are usually studied by different disciplines, yet the first quietly records the second: lead deposition in Greenland ice cores derives largely from the atmospheric fallout of Roman smelting, and because silver was refined from lead-rich…

Fracture physics and Viking economics meet in the hack-silver hoard. When brittle materials are broken repeatedly and more or less at random, the resulting fragment masses follow a universal power-law distribution — a robust result from fragmentation physics that holds for shattered…

Coin hoards and the VIX volatility index are the two well-known things joined here: hoard deposition is antiquity's fear gauge. People bury treasure when they are frightened, and — crucially — they bury on rumor, before armies actually arrive, just as modern…

Gresham's law — bad money drives out good — is here joined to the physics of phase transitions. The conjecture is that the driving-out is not gradual: when rulers debase the coinage, users tolerate the slide in silver fineness up to a…

Circulation velocity — how fast money changes hands, a quantity economists struggle to measure even today — is here read off the physical surfaces of the coins themselves. Every transaction abrades a coin slightly, so cumulative wear divided by time in circulation…

Gibrat's law — the modern finding that firm growth rates are independent of firm size, which generates the Pareto (power-law) distribution of firm sizes seen in every industrial economy — is here tested two thousand years early. Roman brickyards (figlinae) stamped their…

Nominal wage rigidity — the Keynesian observation that wages resist adjustment even when prices move — is here pushed back four thousand years to the ration lists of Ur III Mesopotamia. Ur III institutions paid workers standardized rations of beer and barley,…

Mesopotamian kings periodically proclaimed debt-cancellation edicts — the acts remembered in the biblical Jubilee — and cuneiform loan contracts were physical objects, clay tablets whose destruction voided the debt. Join the two and the conjecture follows: royal debt cancellations should have left…

An astrolabe only works at the latitude its plate is engraved for, so every surviving instrument silently records where its maker expected it to be used. That turns the corpus of surviving astrolabes into medieval market-research data: the set of latitudes engraved…

The modern capital campaign — where a museum or university secures a headline anchor gift or star acquisition just before asking everyone else for money — is here read back into the medieval church. Relic translations, the ceremonial installation of a saint's…

The Polya urn — the classic mathematical model of path dependence, in which each ball drawn adds another of its color so that early luck compounds forever — is here applied to the medieval pilgrimage market. Pilgrims bought cheap metal badges at…

Currency unions are supposed to be a modern invention, and low variance in the unit of account is their hallmark: struck coinage keeps its weight uniform because mints are policed. The trans-Saharan trade, by contrast, ran for centuries on bars of rock…

Great Zimbabwe on its inland plateau and the Swahili port of Kilwa on the Indian Ocean coast are the two famous sites joined here, and the joint is metrological. Kilwa struck its own coins to a known weight standard and shipped the…

The lender of last resort — Bagehot's celebrated principle that a central bank should lend freely when private credit dries up — is here sought in the Old Babylonian credit market, more than three millennia before the Bank of England. Babylonian lending…

The backward-bending supply curve — the textbook anomaly in which workers with an income target respond to falling prices by working more, not less — is here joined to the fate of Norse Greenland. The colony's export staple was walrus ivory, and…

The gravity model of trade — flows decay with distance, and how steeply they decay depends on what the goods are worth relative to what they cost to move — is here tested on sourced ancient artifacts. Provenance science can trace both…

In the 13th century, English law adopted a rule for how far apart markets must be — the spacing derived in the classic legal reckoning from a day's return journey on foot, about 6.6 miles. The conjecture joins this statute to the…

Joins index-number theory — the chained construction behind the modern consumer price index — to Tamil temple epigraphy. Thousands of dated Chola-era endowment inscriptions record in stone the rates of paddy, ghee, and oil required to keep a temple lamp burning in…

Joins the economics of luxury counterfeiting to Japanese sword connoisseurship. Counterfeiters allocate effort where brand equity is highest — today's fakes concentrate in the top handbag brands, not the mid-market — because the payoff to a forged label scales with the premium…

Joins actuarial insurance pricing to maritime archaeology. A fourth-century BCE Athenian bottomry loan was repaid only if the ship survived the voyage, so the premium over ordinary land-secured interest is a pure risk price: if lenders broke even, the spread directly encodes…

Joins the economics of protection rackets to Han-Xiongnu diplomacy. A racketeer prices extraction to the victim's outside option: what matters is not how hard the racketeer can hit but how badly the victim needs quiet, so payments ratchet up when the victim…

The term structure of interest rates — the yield curve — normally slopes upward, because lenders demand compensation for longer exposure to risk. This conjecture says Old Assyrian merchant finance in the Kanesh trade refused that logic: interest in the Kultepe loan…

Price-ceiling economics predicts that goods capped below market price withdraw from legal, recorded exchange, while goods capped at or above market trade on visibly. This conjecture reads Diocletian's Price Edict of 301 CE through that lens: the Edict's famous failure should be…

Absenteeism econometrics has two robust modern findings: absence hazard spikes on workdays adjacent to rest days, as workers manufacture long weekends, and total absence is dominated by a small cadre of chronic absentees. This conjecture claims the pharaoh's own tomb-builders behaved identically…

Proof-of-work monetary theory says a currency's value can rest on verifiable production difficulty; this conjecture reads Yapese stone money as its pre-modern instance. Rai stones were quarried overseas and sailed to Yap, and the quarrying-and-transport work embodied in a stone scales faster…

Common-value auction theory predicts the winner's curse — the highest bidder is the one who most overestimated the shared value — and that experienced bidders learn to shade their bids downward. This conjecture finds the earliest documented correction in Venetian state finance:…