The bet that tested whether humanity is running out of everything

Overview

Updated May 30

In 1980, biologist Paul Ehrlich—who had warned that hundreds of millions would starve to death in the 1970s—agreed to bet economist Julian Simon on the price of five commodity metals. If inflation-adjusted prices rose over the decade, Ehrlich wins; if they fell, Simon wins.

On October 11, 1990, Ehrlich mailed Simon a check for $576.07. Every single metal had gotten cheaper.

The wager distilled a two-century-old argument into a falsifiable claim. Ehrlich represented the Malthusian view that a growing population devours finite resources until scarcity forces a reckoning. Simon represented the opposite: that more people means more minds solving problems, finding substitutes, and driving prices down through ingenuity.

The check settled the bet, but not the debate—subsequent research showed the decade Ehrlich picked happened to be unusually favorable to Simon, and metals would have risen in many other windows.

Why it matters

This wager still shapes how policymakers weigh population growth against resource limits when designing environmental and economic policy.

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Key Indicators

$576.07

Ehrlich's payout to Simon

The inflation-adjusted net loss on a $1,000 basket of five metals over ten years

36%

Real price decline of the five-metal basket

All five metals — copper, chromium, nickel, tin, and tungsten — fell in inflation-adjusted terms between 1980 and 1990

5 of 5

Metals that fell in price

Ehrlich chose the metals, yet every one moved in Simon's predicted direction

~62%

Decline in tin and tungsten prices

The two most dramatic drops in the basket, driven by substitution and new mining technology

Voices

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People Involved

Paul R. Ehrlich

Bing Professor of Population Studies, Stanford University

Lost the wager; continued advocating for population-control policies

Julian Lincoln Simon

Professor of Economics, University of Maryland

Won the wager; died February 8, 1998

John P. Holdren

Energy and resources researcher, University of California, Berkeley (at time of bet)

Later served as White House Science Advisor under President Obama (2009–2017)

John Harte

Professor of Ecosystem Sciences, University of California, Berkeley

Active in ecological research

Organizations Involved

Club of Rome

International Think Tank

Provided intellectual backdrop for scarcity arguments

An international organization of academics, business leaders, and policymakers that commissioned the influential 1972 report The Limits to Growth.

Timeline

January 1798 February 1998

7 events Latest: February 8th, 1998 · 29 years ago

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February 1998
Julian Simon dies at age 65
Latest Death

Simon dies of a heart attack in Chevy Chase, Maryland. He had continued to challenge Ehrlich to a second wager, but the two could never agree on terms.
February 8th, 1998
October 1990
Ehrlich mails Simon a check for $576.07
Resolution

All five metals declined in inflation-adjusted price over the decade. The basket fell 36% in real terms. Ehrlich sends payment without a personal note.
October 11th, 1990
January 1981
Simon publishes The Ultimate Resource
Publication

Simon lays out his argument that human ingenuity is the 'ultimate resource,' and that population growth drives innovation that makes raw materials cheaper over time.
January 1st, 1981
September 1980
Simon and Ehrlich formalize the commodity wager
Agreement

Ehrlich, Holdren, and Harte choose five metals — copper, chromium, nickel, tin, and tungsten — and bet Simon $1,000 that their inflation-adjusted prices will rise over the next decade.
September 29th, 1980
March 1972
Club of Rome publishes The Limits to Growth
Publication

A team of researchers at the Massachusetts Institute of Technology uses computer modeling to project that industrial civilization will exhaust key resources within a century if growth continues unchecked. The report sells 30 million copies.
March 1st, 1972
May 1968
Paul Ehrlich publishes The Population Bomb
Publication

Ehrlich predicts that hundreds of millions will starve in the 1970s due to overpopulation. The book becomes a bestseller and galvanizes the environmental movement.
May 1st, 1968
January 1798
Malthus publishes An Essay on the Principle of Population
Publication

Thomas Malthus argues that population grows geometrically while food production grows only arithmetically, predicting inevitable famine. His framework shapes resource-scarcity debates for the next two centuries.
January 1st, 1798

Historical Context

3 moments from history that rhyme with this story — and how they unfolded.

1798

Malthus's Essay on the Principle of Population (1798)

Thomas Malthus, an English clergyman and economist, argued that population doubles roughly every 25 years while food production grows only incrementally. He predicted that famine, disease, and war would inevitably check population growth unless people exercised 'moral restraint' by marrying later and having fewer children.

Then

The essay shaped British social policy, influencing the Poor Laws and debates over welfare. It also profoundly influenced Charles Darwin's theory of natural selection.

Now

The agricultural and industrial revolutions shattered Malthus's arithmetic. Global population grew from 800 million to over 8 billion while per-capita food production and incomes rose dramatically. But 'Malthusian' became a permanent label for scarcity-based thinking.

Why this matters now

Ehrlich was explicitly updating Malthus for the 20th century. Simon was explicitly arguing that Malthus had been wrong for a specific, repeatable reason: human ingenuity responds to scarcity by innovating. The wager was a direct empirical test of the Malthusian framework.

1972

The Limits to Growth report (1972)

A team at the Massachusetts Institute of Technology, commissioned by the Club of Rome, used computer modeling to project that unchecked industrial growth would exhaust key resources and trigger societal collapse by the mid-21st century. The report sold 30 million copies and became a foundational text for the environmental movement.

Then

The report fueled the 1970s environmental policy wave, contributing to the creation of agencies like the United States Environmental Protection Agency and catalyzing international environmental diplomacy.

Now

Many of its specific resource-depletion timelines did not materialize, and critics pointed to its failure to account for price-driven substitution and technological change. But its broader framing — that exponential growth on a finite planet has limits — remains central to sustainability discourse.

Why this matters now

The Limits to Growth created the intellectual climate in which the Simon-Ehrlich wager became meaningful. Ehrlich's side of the bet was essentially the Limits to Growth thesis applied to five specific metals. Simon's side was a direct rebuttal: markets and ingenuity would prevent the projected scarcity.

1960s–1970s

The Green Revolution (1960s–1970s)

Agricultural scientist Norman Borlaug and colleagues developed high-yield, disease-resistant wheat and rice varieties. Combined with synthetic fertilizers and irrigation, these innovations dramatically boosted food production in India, Mexico, Pakistan, and other developing nations. Borlaug received the Nobel Peace Prize in 1970.

Then

India went from famine risk to grain self-sufficiency within a decade — directly contradicting Ehrlich's 1968 prediction that India 'couldn't possibly feed two hundred million more people by 1980.'

Now

The Green Revolution is estimated to have saved over a billion lives from starvation, though it also introduced new dependencies on chemical inputs and groundwater. It became the single most powerful piece of evidence that technological innovation can outrun Malthusian constraints.

Why this matters now

The Green Revolution was happening in real time as Ehrlich published The Population Bomb. It demonstrated exactly the mechanism Simon would later champion: human ingenuity responding to scarcity signals with transformative innovation. It also showed why Ehrlich's most specific predictions failed.