William Stanley Jevons

William Stanley Jevons is the economist who trusted his data more than his hopes. In 1865, when Britain was drunk on industrial optimism, the thirty-year-old Jevons published The Coal Question, a book dense with production figures and consumption statistics proving something nobody wanted to hear: that James Watt’s improved steam engine, which consumed a third of the coal the Newcomen engine had, had not conserved coal—it had made coal useful for applications that had been economically impossible before, and total consumption had tripled. “It is wholly a confusion of ideas to suppose that the economical use of fuel is equivalent to a diminished consumption,” he wrote, as flatly as a mathematician. “The very contrary is the truth.” That single inversion—the Jevons Paradox—is the cleanest lens we have for understanding what happens when AI makes cognitive labor cheap: it does not reduce the demand for cognitive labor, it expands it. Six years later Jevons