The debate team defined my high school experience. I spent weekends traveling to debate tournaments across the country. I faced off against other students on weighty topics like whether justice required the recognition of animal rights or whether juveniles could be treated as adults if they committed violent crimes. Regardless of the topic, which changed every few months, every debater started their arguments with an ethical framework from which to view the round. Winning the framework meant arguing over whether moral systems like utilitarianism[1] or deontology[2] were the best way to decide what was just, or moral. I came away with an appreciation for how difficult it is to build a strong moral system which can resolve the conflicts between two competing values, like protecting the environment or promoting economic growth.
Population Bomb or Ultimate Resource?
Paul Sabin’s book The Bet describes the trade-offs between the economy and environment via the lens of the debate over whether humans were overpopulating the planet and exhausting the Earth’s natural resources. Sabin begins with the rise of the charismatic Stanford biologist Paul Ehrlich, who rose to fame through his forecasts of doom via books like The Population Bomb, published in 1968, and appearances on The Tonight Show with Johnny Carson. After being featured three times in four months in 1970, Ehrlich grew a population control organization called Zero Population Growth to over 80 chapters across the US.
Ehrlich struck a vein within society - as he gained popularity, US political leaders like Richard Nixon started to take environmental policy seriously for the first time. Nixon created the Environmental Protection Agency in 1970 in response to bipartisan pressure to clean up the environment. Ehrlich’s star grew[3] throughout the 1970s as price inflation and concerns about overpopulation continued to grow. The election of President Jimmy Carter put an environmental champion in the White House. Carter advocated that Americans consume less energy and resources, and directed investment into in early versions of solar power and other renewables.
Julian Simon, a little-known business professor at the University of Illinois, watched in frustration for years during the 1970s as Ehrlich gained popularity. Simon believed that a larger population led to more ideas, more innovation and more economic growth, all of which were key to human flourishing. Simon believed there was no basis for Ehrlich’s claims of impending doom due to overpopulation, and called Ehrlich out publicly in 1980 for his lack of accountability for his predictions. Simon offered Ehrlich a chance to put some skin in the game. Simon wagered Ehrlich that prices would fall for any raw material Ehrlich wished to bet on over any time period.[4]
Ehrlich accepted publicly in 1980 and entered into a ten-year bet with Simon for a thousand dollars of contracts[5] for five key commodities: copper, tin, nickel, chromium, and tungsten. Ehrlich believed that a rising population and greater demand would force prices higher; Simon believed that technological innovation and market forces would drive prices down, particularly relative to incomes, as they had since the beginning of the Industrial Revolution. Via the terms of the bet, Simon was effectively short the commodities – if prices went up, adjusted for inflation, he would pay the difference to Ehrlich, and if prices declined, Ehrlich and two colleagues would pay the difference to Simon. While the most Simon could win was $1,000, his downside (and therefore Ehrlich’s upside) was uncapped.

At the start of the bet, Ehrlich was a well-known author and speaker heading a movement with real political momentum in Washington D.C., while Simon was an obscure business professor with no real influence. Things would change dramatically as the bet ran its course. Simon’s publication of The Ultimate Resource, his magnum opus on how “human resourcefulness and enterprise could meet impending shortages and solve problems indefinitely” in 1981 vaulted him to a level of influence Ehrlich alone had previously wielded. The political tailwinds supporting environmental regulation ended abruptly with the election of Ronald Reagan in late 1980, who called for a more pro-growth agenda capitalizing on the US’s natural resources. Now it was Simon who was sought by politicians and policy leaders in in D.C., where he moved with his family.
The scientific consensus moved against Ehrlich too. The National Research Council published a report in 1986 which repeatedly cited Simon and his arguments while calling Ehrlich’s and other claims about overpopulation “exaggerated.” The report’s conclusion, per Sabin, was that "the scarcity of exhaustible resources is at most a minor constraint on economic growth in the near to intermediate term."
And Ehrlich lost the bet. He sent a check for $576.07 (with no note) to Simon in October 1990. Sabin notes, “Simon had prevailed in their bet, by every measure. Despite a record increase in the world population from 4.5 to 5.3 billion people, the prices of the five minerals-chromium, copper, nickel, tin, and tungsten-had fallen by an average of around 50 percent.”[7]
The resolution of the bet in Simon’s favor did nothing to resolve the conflict between Simon and Ehrlich’s views, however. They corresponded in 1990 about a renewed bet, though there was never any agreement over how the bet should be structured. Ehrlich wanted to focus on measures like CO2 emissions, global temperatures, and tropical forest area, while Simon suggested life expectancy and purchasing power, among other metrics.
Sabin concludes by noting that both Simon and Ehrlich made important intellectual contributions to policy during their careers. Ehrlich’s focus on controlling pollution helped spur passage of important regulations like the Clean Air Act and Clean Water Act. Simon correctly highlighted that fears of overpopulation were overblown because human beings can respond to their environments rationally. We adjust resource usage in response to scarcity and abundance and solve problems through new innovations. More humans can live higher quality and more prosperous lives than Ehrlich thought.
Neither Ehrlich nor Simon ever wavered in their convictions, however, and so Sabin ends a history of environmental theory and economics with a pivot towards philosophy. The debate over how to balance environmental and economic concerns is troubling because each side engaged less and less with the other over time. As any high school debater knows, we need an ethical framework to weigh competing priorities. Sabin’s book demands a companion.
A Search for the Panacea
Tyler Cowen’s book Stubborn Attachments, published in 2018, attempts to tackle the ethical dilemma head on. Cowen, an economist at George Mason, spends 144 pages answering the question: “When it comes to choice, I see some key questions for the individual as well as the collective. Why do we prefer one choice over another? To what extent do we have good reasons for such preferences? Exactly which choices should we make?”
He responds by building a thesis that humans have a moral obligation to help maximize the rate of sustainable economic growth, constrained by an absolute respect for human rights.
Cowen starts with a few basic principles to set the terms of his argument:
"Right" and "wrong" are very real concepts which should possess great force.
We should be skeptical about the powers of the individual human mind.
Human life is complex and offers many different goods, not just one value that trumps all others.” (Page 19)
From this starting position, Cowen develops two other principles. First, a postulate which he calls a “Deep Concern for the Distant Future,” which is what it sounds like – we should focus more on making choices today which will contribute to human flourishing in the future, and avoiding large scale future tragedies. As Cowen puts it:
“We should not count catastrophic losses for much less simply because those losses are temporally distant. In the absence of qualifying factors, no amount of temporal distance per se should cause major widespread tragedies to dwindle into insignificance in the present. We should believe that the end of the world is a truly terrible event, even if that collapse comes in the distant future.” (Page 75)
Cowen complicates our long-term thinking with what he calls “the epistemic critique.” He points out that most of the time, we have no idea what the future will bring, as there is a huge amount of contingency and uncertainty in human affairs. Only a few issues or goals can rise above the uncertainty, and we should focus on those: “Anything we try to do is floating in a sea of long-run radical uncertainty, so to speak. Only big, important upfront goals will, in reflective equilibrium, stand above the ever-present froth and allow the comparison to be more than a very rough one.”
The combination of the importance of the long-term future and the difficulty in seeing that future make Cowen skeptical about the importance of small trade-offs. Instead, Cowen believes we should focus on, to use a phrase from economist Frank Knight, “Crusonia Plants.” Taken from the trees in Daniel Defoe’s Robinson Crusoe, Crusonia plants grow their populations via the seeds of their own germination and are special because they benefit from the long-term impacts of compounding. Growing 3% a year doesn’t seem like much at first, but an island half covered in Crusonia plants will be fully covered in 25 years.
Cowen believes economic growth is a Crusonia plant,[8] as steady, sustainable economic growth can massively increase the wealth and prosperity of a society when viewed over long time scales.
Cowen views wealth as something of a panacea; richer societies can make fewer trade-offs because they can afford to invest in outcomes that make everyone better off – like Oprah or Mr. Beast, they can afford to give everyone a car. They also are more resilient, because they can afford to invest in measures to prevent catastrophic risks – no space program, no way to dodge a killer asteroid - and have more resources to recover when something does go wrong. The magic of long-term compounding and the freedom/resilience provided by wealth are a powerful combination; enough to overcome the epistemic critique.
Cowen spends some time developing his definition of wealth beyond just gross domestic product:
“I will define the concept of Wealth Plus as follows:
Wealth Plus: The total amount of value produced over a certain time period. This includes the traditional measures of economic value found in GDP statistics, but also includes measures of leisure time, household production, and environmental amenities, as summed up in a relevant measure of wealth.
In this context, maximizing Wealth Plus does not mean that everyone should work as much as possible. A fourteen-hour work day might maximize measured GDP in the short run, but it would be less propitious over time once we take into account the value of leisure, not to mention the potential for burnout. Still, this standard is going to value a strong work ethic! Maximizing Wealth Plus also does not mean destroying the natural environment. It's now well understood that environmental problems can lower or destroy economic growth through feedback effects. We should therefore protect the environment enough to preserve and indeed extend economic growth into the more distant future. More broadly, the principle of Wealth Plus holds that we should maintain higher growth over time, and not just for a single year or for some other, shorter period of time. Maximizing the sustainable rate of economic growth does not mean pursuing immediate growth at the expense of all other values.” (Page 30)
Cowen ends with a series of recommendations;[9] included is the request that we more strongly consider the existential risks that threaten civilization, and that we think a little bigger[10] in our goals to promote human flourishing. In pursuing the maximization of Wealth Plus, Cowen argues we need to more to focus on three big problems:
What can we do to boost the rate of economic growth?
What can we do to make our civilization more stable?
How should we deal with environmental problems?
Stubborn Attachments makes a contribution in refocusing on our moral responsibility on long-term goals. But in framing the three questions above, I don’t come away with a strong intuition on how to trade off environmental protections with a higher rate of economic growth. The complexity of Earth’s ecosystems seems to make many decisions susceptible to the epistemic critique – it’s hard to know whether cutting down an incremental tree is more additive to economic growth in the long run by helping create more housing, or subtractive by eliminating a carbon sink.
Sabin ends The Bet with two lines underscoring this issue: “Ultimately, humanity’s course will be determined less by the iron laws of nature or by unbounded market powers, Ehrlich and Simon’s dueling lode-stars, and more by the social and political choices that we make. Neither biology nor economics can substitute for the deeper ethical question: What kind of world do we desire?”
Stubborn Attachments clarifies the important issues brought up by Ehrlich and Simon – we should spend much more time thinking about economic growth and environmental protection – at the expense even of other worthy cases - even if it doesn’t truly resolve the question Sabin poses at the end of the book.[11]
Cowen does have one concrete takeaway for Kyle the high school debater. Debate is a game, and at the end of each round there is a winner and a loser. We argue for the sake of arguing, forcing conflict and trade-offs. This is a lot of fun, but is likely not the right framework for thinking about making the world a better place. Instead, we all ought to allocate more time to searching for and tending Crusonia plants, for the fruits of their harvest will make us all better off.
Read/Skim/Skip:
The Bet:
Read: The introduction, pages 44-51 in Chapter 1, which give you a real sense of the pressures that a conservative Republican Richard Nixon felt and which drove his decisions to create the EPA, Chapter 4 “The Triumph of Optimism,” which outlines The Bet, pages 182-189 in Chapter 5 which describe the outcome, and Chapter 6, “Betting the Future of the Planet,” which includes Sabin’s key conclusions.
Skim: Chapter 1, “Biologist to the Rescue” which is primarily Ehrlich’s biography and role in the early environmental movement, Chapter 2, “Dreams and Fears of Growth” which is primarily Simon’s biography and pushback to the overpopulation thesis, Chapter 3, “Listening to Casandra,” which covers the Carter Administration and the scarcity mindset which was prevalent in the late 1970s, and most of Chapter 5, “Polarizing Politics” which traces the thru-lines between The Bet and current environmental policy and debates.
Skip: None, it’s all worth at least quickly skimming.
Stubborn Attachments:
Read: Everything except Chapter 5, “What about Redistribution?” The book is already short at 144 pages, and Cowen keeps his arguments pretty tight.
Skim/Skip: Chapter 5 is interesting if you’re interested in the limits of an individual’s obligations under a consequentialist framework, but otherwise, one can pass and still get Cowen’s full argument.
An Alternative Reading of The Bet
One of my goals for Book Pairings is to showcase that readers (particularly of non-fiction) can and should free themselves from the tyranny of reading every page of every book in the order they were presented. While The Bet’s structure is primarily chronological, the book can be reconfigured into a Matryoshka doll – a ten-year wager between academics expands to encompass their biographies and contributions to the overpopulation debate and expands again to show how each academic represents a wider political and ideological movement which deeply influenced the course of the last fifty years of US economic and environmental policy.
The Bet:
Start with pages 131-137 (introduction to the bet), then 181-189 (the conclusion), 200-203 on the failure to renew the bet
The Biographies:
Ehrlich: page 10-44, 53-61, 96-103, 115-122, 127-130, 150-152, 172-176, 205-207, 222
Simon: page 62-80, 93-95, 122-126, 152-172, 176-178, 203-205, 207-210
The Movements:
Rising environmental consciousness of the late 1960s/Nixon administration 45-53
Limits to Growth environmentalists start to conflict with economists: 80-93
Jimmy Carter’s and the ascendancy of the conservation mindset: 103-115
Reagan and the pivot to economic growth from environmental conservation: 137-150
Increasing ideological polarization along growth vs. conservation axis & impact on debate over climate change: 189-200, 210-216
Thanks to my On Deck Writers workshop squad (Josh, Kate, Harry, and Manish) for reading multiple drafts and making this significantly better. And thanks to my Mom, my first and greatest editor.
[1] Simplistically, the idea that we ought to maximize the greatest good for the greatest number.
[2] A moral theory which, to oversimplify, prohibited aggregating moral costs and benefits across individuals or groups of people. Immanuel Kant was central to its development in the 18th century.
[3]Though his confident predictions of imminent doom made other academics and scientists uncomfortable with his methods and tactics.
[4] Ehrlich claimed in 1969 that it was an even-money bet over whether England would exist in 2000, thanks to overpopulation causing one of “nuclear war, plague, ecological catastrophe, or disastrous recourse scarcity”
[5] ~$3,300 today, but really the bet was about reputation – the Chronicle of Higher Education called it the “scholarly wager of the decade” (pg. 137)
[6] Photo from Paul Sabin’s The Bet pg. 204/the family of Julian Simon.
[7]A very important caveat – Ehrlich was somewhat unlucky with his timing, even though his overpopulation thesis was flawed. Sabin writes: “when economists later ran simulations for every ten-year period between 1900 and 2008, they found that Ehrlich would have won the bet 63 percent of the time. That did not mean, however, that a longer bet over the course of the century necessarily would have gone to Ehrlich. Rather than a steady increase in prices over the century, the 1900–2008 data showed a precipitous crash in commodity prices after World War I and then a century-long irregular return to World War I levels. The simulations showed Ehrlich prevailing in 63 percent of the ten-year bets largely because prices had plummeted so low in the post-World War I crash.” (Page 189)
[8] Though given the need for a book about how we should adopt policies to promote growth, it’s not clear to me how inherently self-sustaining it really is.
[9] Here’s the full list:
a. Policy should be more forward-looking and more concerned about the more distant future.
b. Governments should place a much higher priority on investment than is currently the case, in both the private sector and the public sector. Relative to what we should be doing, we are currently living in an investment drought.
c. Policy should be more concerned with economic growth, properly specified, and policy discussion should pay less heed to other values. And yes, that means your favorite value gets downgraded too. No exceptions, except of course for the semi-absolute human rights.
d. We should be more concerned with the fragility of our civilization. The possibility of historical pessimism stands as a challenge to this entire approach, because in that view the future is dim no matter what, and there may not be a more distant future we can look toward in order to resolve the aggregation dilemmas involved in making decisions that affect so many human beings.
е. We should be more charitable on the whole, but we are not obliged to give away all of our wealth. We do have an obligation to work hard, save, invest, and fulfill our human potential, and we should take these obligations very seriously.
f. We can embrace much of common sense morality with the knowledge that it is not inconsistent with a deeper ethical theory. Common sense morality can also be reconciled with many of the normative recommendations which emerge from a more impersonal and consequentialist framework.
g. When it comes to most "small" policies affecting the present and the near-present only, we should be agnostic, because we cannot overcome aggregation problems to render a defensible judgment. The main exceptions here are the small number of policies which benefit virtually everybody. (Page 123)
[10] A small irony for an economist with a popular blog called Marginal Revolution.
[11] Cowen does give the reader fair warning on this point at the end of his introduction: He says that, for the kind of reader he wants, “you will feel I have not pushed hard enough on the tough questions, no matter how hard I push.”
Fascinating debate. Especially in current times.