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…

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…

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…

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 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…

Bronze needs tin, and Late Bronze Age tin moved through a long-distance exchange network linking a handful of distant sources to every workshop in the eastern Mediterranean. In network terms, some cities were mere consumers while others were high-betweenness brokers — nodes…

This joins Gothic cathedral construction to the economics of competitive escalation — the same arms-race dynamics seen in armament races and advertising wars. A cathedral's height was a prestige signal aimed at specific rivals, and the relevant rivals were local: the sees…

This joins the moai of Rapa Nui — one of archaeology's most famous statue traditions — to the logic of competitive escalation between rival groups, the same dynamics that drive arms races. If lineages competed for prestige through statue size, each generation…

This joins Wright's law — the industrial learning curve, under which performance improves as a power law of cumulative production — to the humblest of ancient mass products, amphorae and lamps. Wright's law is usually treated as a discovery of twentieth-century aircraft…

This joins ceramic technology to environmental history: kilns, it claims, are unwitting gauges of energy scarcity. Firing pottery to high temperature consumes large quantities of wood, so when a region's forests thin, fuel becomes the binding constraint on the potter's craft. Rather…

This joins Roman economic history to archaeometric chemistry. Fresh Roman glass was made in a handful of great Levantine furnaces and shipped west as raw chunks; when supply chains ran smoothly, workshops melted fresh glass, and when they faltered, workshops fed broken…

This joins medieval church archaeology to geomagnetism. Churches were meant to face east, yet surveyed orientations scatter by several degrees, and the scatter is usually written off as sloppy surveying. But once the magnetic compass entered the building trades — plausibly around…

This joins Roman land surveying to archaeoastronomy. When Rome founded a colony, surveyors laid out the centuriation — the great land grid — around a principal axis, and Roman ritual practice tied foundation ceremonies to specific festival dates. The conjecture holds that…

This joins two of the medieval world's best data series: the Nilometer readings of the Nile's annual flood, kept for centuries at Cairo, and the grain prices preserved in the Cairo Geniza's merchant letters. Egypt's harvest was the flood: a low Nile…

Markowitz's portfolio theory says diversification pays exactly when the assets you spread across are weakly correlated — variance falls fastest where covariance is low. The medieval open-field system's scattered strips, a puzzle ever since they were read as peasant insurance, are a…

Airborne LiDAR has stripped the canopy from the Maya lowlands and revealed settlement in the tens of thousands of structures, making true regional settlement hierarchies measurable for the first time; settlement-scaling theory, meanwhile, holds that integrated urban systems produce Zipfian rank-size distributions…

RT60 — the time a sound takes to decay by sixty decibels — is the basic figure of architectural acoustics, and a great stone nave can hold a note for many seconds; a fast syllabic melody blurs into mud in such a…

Muqarnas — the honeycomb vaulting of Islamic architecture, thousands of small stepped niches filling domes and squinches — is usually read as pure geometry made ornament. But a surface of many differently sized and angled cells is exactly what a modern acoustician…

The Colosseum moved crowds of tens of thousands through its vomitoria — the numbered entrances and radiating stair-and-corridor system that gave the building its famously fast turnover. Modern stadium safety codes make crowd egress a precise engineering quantity: evacuation-time standards, flow rates…

The Polynesian settlement of the Pacific is the greatest search problem ever solved by a preindustrial society, and optimal search theory says how a rational searcher orders targets: not by raw distance, but by how easy each target is to find. An…

The deep blue of medieval stained glass comes from cobalt, and medieval Europe mined very little of it: the colorant travelled along long-distance routes whose ultimate sources lay far to the east. Every ore body carries a trace-element fingerprint — the ratios…

Joins the economics of crime — Gary Becker's principle that offenses rise when their returns rise and legitimate wages fall — to the Deir el-Medina archives of the royal tomb-builders. The workmen were paid in grain, and the ostraca record their ration…

Joins transport-cost linear programming to the Codex Mendoza, the pictorial register of what each Aztec province owed Tenochtitlan. The empire had no draft animals and no wheels: every tribute load moved on a porter's back, so the true cost of a good…

Joins statistical process control — the control charts and capability indices of modern manufacturing — to Andean ceramics. Inca state pottery, above all the standard aryballos storage jar, was the output of an administered production system, so the tightness of its dimensional…

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 process-engineering labor accounting to Viking naval history. Tally the person-hours in a longship and the surprise is that the hull is the cheap part: replication labor budgets show a large woolen sail — the wool sorted, spun thread by thread, woven,…

Joins modern campaign geography to Pompeian electoral epigraphy. Political scientists mapping yard signs and canvassing find both decay with distance from the candidate's home, because campaigns run on the candidate's own network of neighbours, clients, and friends, and that network is spatially…

Joins experience-curve economics to Islamic mathematical geography. In manufacturing, quality improves as a power law of cumulative output — the experience curve — because every unit produced teaches its producers. Every mosque is such a unit: it must face Mecca, its measurable…

Vertical-monopoly pricing from industrial organization shows that a chain of independent monopolists along one route charges more in total than a single owner would, because each ignores the damage its markup does to the others' traffic. This conjecture reads the toll castles…

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…

Service-capacity planning sizes a facility to a fixed fraction of the population it must serve at peak; this conjecture claims Greek cities did the same with their theaters. If theaters were built to seat a set percentile of the citizen body —…

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…

The Four Branches of the Mabinogi, medieval Wales's greatest prose fiction, and the Welsh lawbooks were written down in the same era and copied in the same milieus, yet are read as unrelated genres. This conjecture claims the Four Branches are structured…

Chant scholars know a 'Germanic' melodic dialect exists; linguists know the High German consonant shift drew sharp isoglosses across the same map. The conjecture joins them: the boundary of the Germanic chant dialect should follow vernacular linguistic isoglosses, not the diocesan and…

Medieval miracle collections record two great genres of wonder: the sick healed at the shrine, and the distant devotee — the drowning sailor, the chained prisoner — saved by invocation alone. The conjecture is that the mix is a strict function of…

Indulgences — remissions of penance measured in days and years — famously inflated across the later Middle Ages. The conjecture is that the inflation had exactly one source: canon law capped each bishop's grant at forty days, and that cap held, so…

Early medieval charters routinely ended by cursing violators — anathema, the fate of Judas, eternal fire — while later charters mostly dropped the curses. The conjecture is that the curse was a substitute enforcement technology whose use varied inversely with access to…

A 'noted breviary' packs the whole office, music included, into one volume — an engineering compromise, since choirs preferred specialized books. This conjecture claims the compromise has a demographic address: noted breviaries concentrate in areas of dispersed rural settlement and poor parishes,…

Written polyphony — music in independent parts — appears in some institutions and not others, a distribution usually explained by artistic ambition. This conjecture explains it administratively: notated polyphony arises only in institutions that had already individuated their personnel accounts — paying…

The pilgrimage sanctuary of Banganarti and other Nubian churches carry hundreds of visitors' wall inscriptions — in effect a signed guest register spanning centuries, left by ordinary pilgrims as well as dignitaries. Treated as a traffic counter, the dated and datable graffiti…

Demotic — the everyday Egyptian script with a thousand-year notarial tradition behind it — stops being used for contracts early in Roman rule, and the standard picture blames a slow decline of Egyptian literacy. This conjecture joins the disappearance instead to an…

This conjecture joins the chronology of English famines to the typology of English charters. In subsistence crises smallholders sell land to eat, and the buyer of a desperate seller insists on parchment precisely because hungry men's kin come back to court later;…