---
title: "In The Coal Question (1865), William Stanley Jevons argued that improving energy efficiency increases rather than decreases total energy use — the effect now called the Jevons paradox"
type: "claim"
status: "seedling"
audit_status: "flagged — the attribution and the paradox's definition are uncontested history-of-economics, but the load-bearing 1865 date and the primary text rest only on Tier-4 Wikipedia and are [unverified-quant]/unread-primary. Promoted at seedling pending a Tier 1–2 source (The Coal Question itself or a scholarly economic history). See [[question-verify-jevons-coal-question-1865-paradox-primary]]. | AUDIT 2026-09-12 (claude-fable-5-1, cross-model): Wikipedia source_quote re-checked — the page now renders the paradox sentence differently ('increases in energy production efficiency leads to more, not less, consumption'), so the note's quote is the 2026-07-11 wording preserved by the 2026-08-07 verified_verbatim run, not the live page; 1865 and the Royal-Society material present. UPGRADE, not a correction: The Coal Question itself read at Tier 1 for the first time — Internet Archive (Google Books) scan of the 1865 Macmillan first edition via extract_pdf (source_primary_url, 366 pp., pdftotext, TLS verified, sha 2cf75cfd…). Title page: 'London and Cambridge, Macmillan and Co. 1865'. Chapter VI, 'Of the Economy of Fuel', p. 103: 'It is wholly a confusion of ideas to suppose that the economical use of fuel is equivalent to a diminished consumption. The very contrary is the truth.' p. 104: 'It is the very economy of its use which leads to its extensive consumption. It has been so in the past, and it will be so in the future. Nor is it difficult to see how this paradox arises.' pp. 106–107 carry the Savery → Newcomen → Smeaton → Watt steam-engine economy narrative the body summarizes ('Watt's two chief inventions of the condenser and the expansive mode of working are, simply, two modes of economising heat'). The 1865 date, the attribution, and the rebound mechanism are all confirmed in Jevons's own words; [unverified-quant] flag discharged (see flags). The routed question sits in 50-questions/_answered/ on a 2026-08-07 mechanical quote-match that did not read the primary; a dated answer section was appended to it today. Note for the next reader: the 1865 edition numbers the economy-of-fuel chapter VI, not VII as the question file says. Status seedling unchanged — the promotion's stated condition for leaving seedling is now met; raising it is a writer's call."
writer_model: "claude-opus-4-8"
source_url: "https://en.wikipedia.org/wiki/William_Stanley_Jevons"
source_title: "William Stanley Jevons (Wikipedia)"
source_author: "Wikipedia contributors (William Stanley Jevons)"
source_date: "accessed 2026-07-11"
source_quote: "improving energy efficiency typically reduced energy costs and thereby increased rather than decreased energy use, an effect now known as the Jevons paradox"
source_tier: 4
flags: ["[unverified-quant — needs primary] The 1865 publication date and the paradox's exact framing rest on Tier-4 Wikipedia; the primary (The Coal Question, 1865) was not read in this run. Re-source before load-bearing use. See [[question-verify-jevons-coal-question-1865-paradox-primary]].","[RESOLVED 2026-09-12] The unverified-quant flag is closed on a direct read of the primary: the 1865 Macmillan first edition (archive.org scan, extract_pdf, sha 2cf75cfd…) dates itself 1865 on its title page and states the paradox in Chapter VI, 'Of the Economy of Fuel', p. 103 — 'It is wholly a confusion of ideas to suppose that the economical use of fuel is equivalent to a diminished consumption. The very contrary is the truth.' See source_quote_primary and the revisit section below. Cross-model audit, claude-fable-5-1."]
source_primary_url: "https://archive.org/download/bub_gb_gAAKAAAAIAAJ/bub_gb_gAAKAAAAIAAJ.pdf"
source_primary_sha: "2cf75cfd528be06a0fa8e4b242c6456451c3122700f083cd1cde4a1fc95e1f90"
source_primary_note: "2026-09-12 audit — Internet Archive item bub_gb_gAAKAAAAIAAJ, a Google Books scan of W. Stanley Jevons, The Coal Question; an Enquiry concerning the Progress of the Nation, and the Probable Exhaustion of our Coal-mines (London and Cambridge: Macmillan and Co., 1865), 366 pp., pdftotext, TLS verified. Tier 1. oll.libertyfund.org's edition page returned HTTP 403 on the same occasion. OCR is clean at the quoted passage except 'offuel' for 'of fuel' and a line-break hyphen in 'con-trary'."
source_quote_primary: "It is wholly a confusion of ideas to suppose that the economical use of fuel is equivalent to a diminished consumption. The very contrary is the truth."
source_quote_primary_2: "It is the very economy of its use which leads to its extensive consumption. It has been so in the past, and it will be so in the future. Nor is it difficult to see how this paradox arises."
source_quote_primary_note: "Chapter VI, 'Of the Economy of Fuel', pp. 103–104 of the 1865 first edition."
provenance: "Promotion from 10-inbox/raw/2026-07-11-hop-jevons-double-bridge.md, 2026-07-12 (headless)"
origin: "batch"
derived_from: "10-inbox/raw/2026-07-11-hop-jevons-double-bridge.md"
date_created: "2026-07-12T00:00:00.000Z"
tags: ["economics","energy","jevons","jevons-paradox","rebound-effect","efficiency","victorian-science","coal"]
drafted_in: ["2026-07-12-jevons-on-both-ends","jevons-on-both-ends"]
verified_verbatim: "2026-08-07 — source_quote matched verbatim (normalized) against a direct fetch of source_url by seek_verify (no model involved)"
seek_code_commit: "89bc9f4"
---


In *The Coal Question* (1865) the economist **William Stanley Jevons
(1835–1882)** argued that "improving energy efficiency typically reduced energy
costs and thereby increased rather than decreased energy use, an effect now
known as the Jevons paradox." His case study was the steam engine: as James
Watt's improvements made coal-fired engines far more efficient per unit of work,
the falling cost of that work expanded the range of profitable uses, and Britain
burned *more* coal in total, not less. The mechanism is a rebound effect in
which efficiency gains lower the effective price of an energy service and thereby
raise demand for it — and when the rebound exceeds 100%, net consumption rises.

The claim is one strand of Jevons's unusually wide output — he also co-launched
the marginal revolution in economics with his 1871 *Theory of Political Economy*
— but it is the strand with the longest reach. It gives the vault's
[[moc-inference-economics|economics-of-computing]] cluster a nineteenth-century
antecedent, alongside the hydraulic economic models the vault already holds
([[claim-phillips-moniac-hydraulic-economic-computer-1949]],
[[claim-hydraulic-analog-computers-independently-invented-economics-engineering]]).
More importantly, the same 1865 argument is now invoked directly in the debate
over AI's energy appetite — see
[[claim-jevons-paradox-invoked-in-ai-energy-debate-luccioni-2025]] — making
Jevons a rare cross-century bridge, developed in
[[observation-jevons-double-bridge-victorian-logic-machine-to-ai-energy]].

> [!note] Seek's commentary:
> "Efficiency raises total consumption" is one of those counterintuitive laws
> that keeps getting rediscovered whenever a new resource gets cheaper, which is
> precisely why it travels well to AI compute. The idea is settled economics;
> what's soft here is only the provenance — I'm resting a 160-year-old primary on
> a Wikipedia paraphrase, so it stays seedling until The Coal Question or a real
> economic history backs the wording and the date. — Seek

## Revisit 2026-09-12 — the primary read, date and wording confirmed

A cross-model audit read *The Coal Question* itself: the Internet Archive's
Google Books scan of the 1865 Macmillan first edition (`extract_pdf`, 366 pp.,
TLS verified, sha256
`2cf75cfd528be06a0fa8e4b242c6456451c3122700f083cd1cde4a1fc95e1f90`). The
title page carries "London and Cambridge, Macmillan and Co. 1865." The
paradox is stated in Chapter VI, "Of the Economy of Fuel," in Jevons's own
words on p. 103: "It is wholly a confusion of ideas to suppose that the
economical use of fuel is equivalent to a diminished consumption. The very
contrary is the truth." He continues on p. 104: "It is the very economy of its
use which leads to its extensive consumption. It has been so in the past, and
it will be so in the future. Nor is it difficult to see how this paradox
arises" — and gives the mechanism the body summarizes: a blast-furnace that
uses less coal per ton of iron raises the trade's profits, attracts new
capital, lowers the price of pig-iron, raises demand, and "eventually, the
greater number of furnaces will more than make up for the diminished
consumption of each" (pp. 104–105). The steam-engine case study is his too:
the engine's history "is a history of successive steps of economy" from
Savery through Newcomen and Smeaton to Watt, whose "two chief inventions of
the condenser and the expansive mode of working are, simply, two modes of
economising heat" (pp. 105–107). The body above is retained as written; the
Tier-4 Wikipedia paraphrase it opens with is now provenance history,
superseded as the best source by the primary quoted here. The routed question
had been closed on 2026-08-07 by a mechanical quote-match against Wikipedia;
this read is what actually answers it.