One Thousand and One Conjectures

Price elasticity — the workhorse concept of consumer economics — is here applied to the length of medieval letters. Writing surfaces were a real cost of correspondence: parchment was expensive, and the paper that spread through the medieval Mediterranean made the surface…

Parchment is made from animal skins, so a sheet of vellum is effectively a livestock derivative — every codex embodies a slaughtered calf, sheep, or goat. This ties the medieval book trade to the health of the herd: when a cattle plague…

Medieval Easter tables list several parallel columns — golden number, epact, dominical letter, indiction — each computed from the same underlying calendrical cycles, so any one column can in principle be re-derived from the others. That mutual derivability is exactly the structure…

Scribes routinely closed their work with self-deprecating apologies — “forgive the faults of the unworthy scribe” — and the naive reading treats these as confessions from careless copyists. The claim inverts that: such formulae are costly quality signals, the mark of a…

Monastic scribes copied in the gaps left by the agricultural year, bending to the pen most heavily in the dead of winter when the fields demanded nothing; urban professional copyists, decoupled from farm labour, worked to a flat year-round rhythm driven by…

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…

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…

This joins historical linguistics to campanology. Dialectologists map isoglosses — the boundary lines where one regional speech feature gives way to another — and those lines famously follow the channels of contact: rivers, roads, trade routes. Bell founding, the conjecture claims, worked…

This joins medieval pilgrimage history to tribology, the physics of wear. Every pilgrim who crossed a church threshold removed a microscopic layer of stone, and centuries of feet turned steps into shallow basins; the missing volume is a footfall counter that no…

The Swahili stone towns of the East African coast — Kilwa above all — were built of coral rag set in lime mortar, and construction there was governed by the monsoon: the rains halt building and lime-burning, so work proceeds in an…

The Norse thing — the open-air assembly at which law was recited, cases were pled and decisions proclaimed — was above all an exercise in unamplified speech before a crowd, and sites like Thingvellir have long invited the suspicion that their cliffs…

Joins autocatalytic reaction kinetics to the sociolinguistics of conquest: in Egypt's dated documentary papyri, the replacement of Greek and Coptic by Arabic behaved like a chemical substitution running with a nearly universal rate constant. The mechanism is autocatalytic — every office and…

Joins neutral models of cultural evolution to Byzantine book epigrams — the short verses scribes copied into margins and colophons, catalogued by type in the DBBE. Under the standard rich-get-richer model of cultural copying, an epigram type spreads because scribes copy what…

In asset pricing, the single-factor market model says every stock, however idiosyncratic, loads positively on one common market factor. This conjecture applies it to Eastern Christian book production: the Syriac, Armenian, Coptic, Ethiopic, Georgian and other traditions were doctrinally separated and institutionally…

Phase separation in soft-matter physics says a mixture of immiscible components does not sit stably at half-and-half: it demixes into nearly pure domains, depleting the middle of the composition spectrum. This conjecture applies that instability to monastic geography in the vHMML catalogues…

Priority queueing theory has a textbook pathology: give one class of customers near-absolute priority and their waiting times stay compact while low-priority waits blow up into a heavy tail. This conjecture finds that pathology in the Heian court's promotion ladder as recorded…

Leishu quotation habits should encode the physical access cost of the scroll. A compiler excerpting a source before the late Tang paid a sequential-access price — matter at the head of a juan costs one motion of the roller, matter at the…

Mixtec screenfold painters worked along red guide-lined boustrophedon registers laid out before painting. If composition ran on a short planning horizon, spacing should compress as the painter approaches each register turn — the same crowding-at-the-end signature papyrologists read in line justification —…