Hot topic: nickel was one of the five metals at the heart of a crucial wager (Image:Jean Guichard/Corbis)

Paul Sabin reveals the huge repercussions of a wager in The Bet: Paul Ehrlich, Julian Simon, and our gamble over Earth’s future

THIS was a brilliant idea for a book. In The Bet, Paul Sabin has produced an absorbing narrative of how two people’s “clashing insights” unleashed on the world polarised views of the environmental and resource threats we face in the 21st century. It culminated in what one normally staid journal called “the scholarly wager of the decade”.

On one side stood Paul Ehrlich, a population biologist from Stanford University in California. Almost half a century ago, he introduced the world to the idea of the population bomb through his bestselling book of that name. On the other side was economist Julian Simon. He was an early acolyte of Ehrlich but came to take an opposite, almost naively optimistic, view.


Their clashes became legendary with Ehrlich, the showman equally at home as a public figure and intellectual pugilist, up against Simon who, although just as combative, was introverted and prone to depression. The invective crackles through the book and remains chillingly relevant today.

Ehrlich’s population bomb was first dropped in the pages of New Scientist on 14 December 1967. His article, entitled “Paying the Piper”, began: “The battle to feed humanity is over… Sometime between 1970 and 1985 the world will undergo vast famines – hundreds of millions of people are going to starve to death.” Human numbers, he said, would double in a generation and we had no chance of feeding everyone.

That article was reprinted in The Washington Post. And, as Sabin explains, at the prompting of the head of the nascent environment group Friends of the Earth, it grew into a 120-page book that eventually sold 6 million copies. Thomas Malthus had raised similar population fears more than a century before, but Ehrlich found the G-spot for a new generation who grew up fearing environmental disaster more than the bomb. Essentially, Ehrlich was Malthus for hippies. Sabin charts the rise of the mercurial, charismatic Ehrlich, who, now in his 80s, is still active in the same debates.

Ehrlich found the G-spot for a generation fearing environmental disaster more than the bomb

The story of Simon is as riveting. He researched marketing at the University of Illinois, Chicago, and was enough of an Ehrlich fan to have written pamphlets on how to persuade women to have fewer children. But emboldened by the free-market rhetoric of that city at the time, Simon eventually became sceptical. With the zeal of a convert, he set out to subvert Ehrlich’s doomwatch.

Simon, says Sabin, declared that there were “no limits to growth”. Ehrlich might be right that more people meant more mouths to feed, argued Simon, but they also delivered “more hands to work and brains to think”. As the title of his 600-page riposte to Ehrlich implied, humans were The Ultimate Resource.

Initially, says Sabin, “the path to [the] bet led through… intellectual jousting of scholarly journals and newspaper op-ed pages”. But the antagonism grew. In 1980, the economist challenged the biologist to a wager.

Simon said he would bet that $1000 worth of five metals – chrome, copper, nickel, tin and tungsten, then all in increasingly short supply – would fall in value during the 1980s. Ehrlich accepted the bet, saying prices were bound to rise. Whoever won would compensate the other for the change in price.

A lot was riding on the outcome. It wasn’t just metal prices; two views of Earth’s future were going head to head. There was an inescapable political context, too. The US president at the time, Jimmy Carter, was an ardent environmentalist who pushed US funding for population control programmes. But the man who beat him in the presidential election later that year, Ronald Reagan, was a free-marketeer, anti-environmentalist and passionate opponent of Uncle Sam paying for family planning services.

Sabin charts how Ehrlich’s star fell while that of his chief protagonist rose. And when the decade ended, Simon came out the victor. Over the decade, world population had grown by 800 million, and the global economy boomed. Yet, counter-intuitively for many, the prices of the five metals had fallen by more than 50 per cent. It was, says Sabin, “the triumph of optimism”.

The resource crunch that should have pushed up metal prices turned out, as Simon predicted, to be an illusion. Innovation and market forces ensured that plastics, fibre optics, ceramics and aluminium supplanted the wager’s chosen metals. In October 1990, Ehrlich mailed a cheque to Simon for $576.07. Tellingly, Sabin says, Ehrlich did not even include a note, still less admit he was wrong. Instead he publicly compared Simon to the man who jumps off the Empire State Building and shouts halfway down that everything is going fine.

While Sabin crafts a fine tale of the contrasting personalities and views of the protagonists, he does not neglect their interesting common ground. Both men believed deeply that they were engaged in the great intellectual battle of the age. And both combined polemic with scholarship to deliver great clarity in their messages.

On a more personal note, Sabin discovers that they were born within a few months and a few miles of each other, into similar Jewish communities around Newark, New Jersey.

He is very aware of their weaknesses. For example, he notes how Ehrlich’s claimed leftist leanings did not protect him from charges of racism over his depiction of “over-breeding” nations while ignoring how rich nations monopolised the world’s resources. Thanks to Sabin, both men are well situated in their political times, but it is a shame that he gives no context beyond the US for their work and views. After all, their influence has been global and it would have been nice to see that explored.

Since the publication of The Population Bomb, two things have derailed Ehrlich’s predictions of famine and a resources crunch.

First, world population has not continued on the exponential trajectory that caused him to call for compulsory birth control. Today’s women are having half as many children as in Ehrlich’s time, under 2.5 each according to current UN figures. As a result, the number of children in the world is believed to have peaked.

And second, so far at least, Simon has been proved largely right about human ingenuity. On food, agriculturalists pushed forward the “green revolution” of high-yielding crop varieties, and have kept food production ahead of population growth.

But the irony is that it was Ehrlich’s chilling predictions that helped deliver that revolution, and encouraged the search for alternatives to depleted metals. His propaganda skills helped him to lose the bet. Equally, without Simon-style optimism that problems have solutions, doom-mongering can become a self-fulfilling prophesy. We need both perspectives.

Ultimately, Sabin is a bit cynical about the bet. He concludes that it was a toxic polarisation of what should have been a more nuanced and measured debate, and it brought out the worst in both men. He sees its “pernicious” effect in the continuing American slugfest over climate change.

I am not so sure. Certainly, it did not resolve the argument. If Ehrlich had bet over 30 years instead of a decade, he would have won – although Simon died too soon (1998) to have paid out. But the issues behind their confrontation remain at the heart of environmental debates on global issues, from protecting ecosystems to feeding the world and combating climate change.

Will every technological advance only hasten Malthusian apocalypse? Or will humanity – all those billions addressing the great problems of the age – come out on top? Ehrlich and Simon’s bet of three decades ago remains our bet today.

The Bet: Paul Ehrlich, Julian Simon, and our gamble over Earth’s future Paul Sabin Yale University Press

This article appeared in print under the headline “Betting with our lives”