Ars Inquirendi

← All conjectures · Book economics & scribal labour

The thousand-year price of a plain book

Status: Anticipated in print · untested

Status is derived only from the shepherd-authored triage/prediction data above -- community submissions and claims are a separate overlay and can never change it (see the participation panel below).

This is a conjecture imagined by a language model — drawn from its trained weights and held to falsifiability, novelty, and plausibility, not to any one method: it may join two or more fields, or none. It is not an article and not evidence: it sits below the evidence/publication boundary. A quantitative prediction and a named kill-dataset are attached (when registered) so the claim stays falsifiable rather than merely evocative.
“Anticipated in print” means the direction of this claim already appears in scholarship, while this exact test has never been run — it records prior art, not proof; nothing here counts as supported or falsified until a registered resolution says so.

Claim (verbatim)

Everyone knows books were expensive before print and cheap after; the standard picture adds a slow medieval cheapening in between. Join the ancient and medieval price records instead into one series and the conjecture is starker: measured in unskilled day-wages, a plain working copy of a standard-length text cost roughly the same in Roman Egypt as in fifteenth-century Italy — a flat real price across more than a millennium, three scripts, and three writing materials. The mechanism is that labour dominated the cost of any book and the human hand's copying speed was a biological constant no organizational change could move, so no pre-print economy could push the real price down. If the conjecture holds, the entire pre-print era becomes a single price regime, and every story of gradual cheapening before Gutenberg breaks.

Prediction clause (verbatim)

Primary clause (carries the verdict): the price of a plain, undecorated copy of roughly 200 leaves' worth of text falls within a single 30-100 unskilled-day-wage band in every region-century cell with usable data, from Roman Egypt to 15th-century Europe, with no statistically significant monotonic downward trend across the pre-print cells. Secondary clause: within-century variance across places exceeds the variance of century means, i.e. geography mattered more than progress.

Kill-dataset (verbatim)

papyri.info (in-house) for ancient book prices and wages; SfarData fee-bearing colophons; SDBM sale prices with published wage deflators; the kill is a statistical trend test across the assembled cross-era series.

Nobody has run this test. The kill-data is named above. If you can run it — or you know the paper that already settles it — claim the kill or submit the prior scholarship. Kills and prior scholarship are credited here, by name, as they come in.

On Inferpedia

This conjecture is linked to the following pages on Inferpedia, an encyclopedia of the missing — working atlas pages, some still early scaffolding.

Provenance

Run: Fresh agent generation · model: claude-fable-5

Composed blind from the model's own knowledge in a zero-tool session and emitted directly as final text.

Novelty / leakage triage

anticipated in the literature — this exact test has never been run

Era-specific book-cost studies exist (Bell et al. for England; Skeat for antiquity) and the labour-dominated, fixed-hand-speed mechanism is understood, but no one has assembled the cross-era series to test the strong claim of a flat 30-100 day-wage real price with no monotonic pre-print trend.

Sources cited by the triage

Predictions

No prediction registered yet.

Weigh in

No community feedback yet.

New here? Create an account first

Create an account or sign in and your feedback is tied to you — you can track it, get replies, and claim this conjecture so others know you’re working on it. Prefer not to? Just leave your take below as a guest — only the name you type is shown.

Add your take

Posted immediately (spam is removed). Community feedback is never an adjudicated verdict and never changes this conjecture's triage label or status above.