What do you call a man who builds a wooden machine to think for him — and then decides the human brain was never anything more than that machine to begin with?

In January 1870, William Stanley Jevons carries his invention into Burlington House, nervous that the Royal Society will laugh him off the stage. They don't. The thing he's built — the Logical Piano, made of rods, levers and pulleys by a clockmaker in Salford — can draw logical conclusions on its own. And if a machine can think, Jevons starts to wonder, what exactly is the human brain doing differently?

What happens to free will once a man's actions are just the output of a calculation? Why does a philosopher gathered with friends at a Cambridge vicarage stand up and say the whole picture is built on sand? And why does Jevons, a free-market man to his bones, end up arguing for public libraries and schools for the poor?

Along the way: a football match that explains the entire theory of wages, a teenage diary entry from the slums of Spitalfields, and a phrase — "a pleasure-seeking machine" — that will outlive everyone in the room.

History of Economic Species tells the story of the evolution of its main character, Homo Economicus. This is the second half of chapter two.

Follow History of Economic Species

• Facebook: https://www.facebook.com/profile.php?id=61592785186292
• Instagram: @historyofeconomicspecies
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Music and audio

• "Good Times", "Blammo", "By Grace" and "Lode Runner" by Podington Bear, via Free Music Archive, licensed under Attribution-NonCommercial 3.0 Unported (CC BY-NC 3.0)
• "CronoCrono", "Hardboil", "Journalistic", "Simos Harbor" and "Vernouillet" by Blue Dot Sessions, licensed under Attribution-NonCommercial 4.0 International (CC BY-NC 4.0)
• "Soul Skip" by Ketsa, via Free Music Archive, licensed under Attribution 4.0 International (CC BY)
• "Wildflowers" by Scott Buckley, licensed under a Creative Commons Attribution 4.0 International License

Voice over by Oliver Morrell, via Fiverr

Sources quoted in this episode

• Edgeworth, Francis Ysidro. Mathematical Psychics. 1881.
• Jevons, William Stanley. "On the Mechanical Performance of Logical Inference." Philosophical Transactions 160, 1870.
• Jevons, William Stanley. The Coal Question. 1865.
• Jevons, William Stanley. The Theory of Political Economy. 1871.
• Jevons, William Stanley. The State in Relation to Labour. 1882.
• Jevons, William Stanley. Letters and Journal of W. Stanley Jevons. 1886.
• Sidgwick, Henry. The Methods of Ethics. 1874.
• Henry Sidgwick: A Memoir. 1906.

What happens when the man who built Homo Economicus refuses to read the book that tries to take him apart?

In 1851, Britain throws the biggest party the world has ever seen — the Crystal Palace, half a kilometre of iron and glass, stuffed with everything the richest nation on earth can make. Homo Economicus strolls through it like he owns the place. Fifteen years later, a young economist named William Stanley Jevons stands up in Cambridge and says Mill got it all wrong: the economy isn't a story about human nature, it's a machine — and it runs on coal that will one day run out.

Why would a man who grew up watching his own family go bankrupt end up throwing weights across a room to measure fatigue? What does a strapping shop in Spitalfields have to do with calculus? And why does Mill, who praised Jevons's book in Parliament, refuse to even open his next one?

Along the way: Queen Victoria marvels at a sugar-purifying machine, a chemist starts timing how tired his own arm gets, and the question of whether a worker is lazy — or just exhausted — starts to matter.

History of Economic Species tells the story of the evolution of its main character, Homo Economicus. This is the first half of chapter two.

Follow History of Economic Species

• Facebook: https://www.facebook.com/profile.php?id=61592785186292
• Instagram: @historyofeconomicspecies
• X: @KenEaron
• Email: HistoryOfEconomicSpecies@gmail.com

Music and audio

• "Good Times" by Podington Bear, licensed under Attribution-NonCommercial 3.0 Unported (CC BY-NC 3.0)
• "Firelight Child", "Tamarinda", "Tyrano Theme", "Thoughtless Machine", "Slimheart", "Delham Corner", "Etude 9 Stefan", "Cabarnet" and "The Poplar Grove" by Blue Dot Sessions, licensed under Attribution-NonCommercial 4.0 International (CC BY-NC 4.0)
• "Aphelion" by Scott Buckley, licensed under a Creative Commons Attribution 4.0 International License
• "Work Wonders (ID 999) – Remastered" by Lobo Loco, licensed under Attribution-NonCommercial-ShareAlike 4.0 International (CC BY-NC-SA 4.0)

Voice over by Oliver Morrell, via Fiverr

Sources quoted in this episode

• Bagehot, Walter. "The Postulates of English Political Economy." 1876.
• Engels, Friedrich. The Condition of the Working Class in England. 1845.
• Jevons, William Stanley. The Theory of Political Economy. 1871.
• Mayhew, Henry. "Labour and the Poor." The Morning Chronicle, 1850. Reprinted in Voices of Victorian London.
• Mill, John Stuart. Principles of Political Economy. 1848.
• Victoria, Queen. Journal entry, 1 May 1851. Royal Archives (via queenvictoriasjournals.org).

What happens when the man who invented a hero built on greed can't stop crying at a Wordsworth poem?

At twenty, John Stuart Mill asked himself a question that broke him for months. By thirty, he was building Homo Economicus — a man driven by one thing only, wealth — and arguing that poetry, music and the circus don't count as economic life at all.

How do you turn a person into a science? Why does watching an acrobat on a galloping horse not count as "doing economics", but making violins does? And what does any of this have to do with a Cambridge scientist, a circus in Rochdale, and a philosopher named Bentham who thought morality could be measured like hay?

Mill knew Homo Economicus wasn't a real man. He just needed him to work.

History of Economic Species tells the story of the evolution of its main character, Homo Economicus. This is the second half of the first chapter.

Follow History of Economic Species

• Facebook: https://www.facebook.com/profile.php?id=61592785186292
• Instagram: @historyofeconomicspecies
• X: @KenEaron
• Email: HistoryOfEconomicSpecies@gmail.com

Music and audio

• "Good Times" and "Squiggly Line" by Podington Bear, licensed under Attribution-NonCommercial 3.0 Unported (CC BY-NC 3.0)
• "Organze", "Crimped Connection", "Levinnia" and "Ghost Byzantine" by Blue Dot Sessions, licensed under Attribution-NonCommercial 4.0 International (CC BY-NC 4.0)
• "Rise Above" and "Golden Hour" by Scott Buckley, licensed under a Creative Commons Attribution 4.0 International License
• "Entrance of the Gladiators, Op. 68" (1897) by Julius Fučík, performed by Eastern Wind Symphony, licensed under Attribution-NonCommercial 3.0 Unported (CC BY-NC 3.0)
• "Loose and Lazy Blues" by ShidenBeatsMusic
• Excerpt from The Old Curiosity Shop by Charles Dickens (1812–1870), read by Mil Nicholson, from LibriVox audiobooks

Voice over by Oliver Morrell, via Fiverr

Sources quoted in this episode

• Bentham, Jeremy. A Fragment on Government. 1776.
• Carlyle, Thomas. On Heroes, Hero-Worship, and the Heroic in History. 1841.
• Dickens, Charles. The Old Curiosity Shop. 1841.
• Mill, John Stuart. "On the Definition of Political Economy and the Method of Investigation Proper to It." 1836.
• Mill, John Stuart. Autobiography. 1873.
• Whewell, William. Letter to J. D. Forbes, 14 July 1831.