Paul Ehrlich, the scientist who scared the planet with his explosive 1968 book, has died / 'He was wrong about everything'

Paul Ehrlich, the Stanford University biologist whose bleak predictions about population growth, global hunger and environmental collapse grabbed headlines and sparked controversy for decades, has died, The Conversation reports.

The researcher “was wrong about everything,” notes the liberal-leaning daily The Los Angeles Times. The publication points out that “it is difficult to overstate the influence that Paul Ehrlich and his followers had on elite opinion and the collective imagination.”

The National Review, the most prestigious conservative magazine in the US, gives the same verdict and writes about Ehrlich's “disastrous legacy”, while The Wall Street Journal notes that he was “always wrong, but never self-doubt”.

The Conversation paints a somewhat more balanced portrait of him, recalling that Ehrlich was one of the most prominent figures in the environmental movement and that he was admired and often honored for his warnings considered by some to be “visionary”.

Ehrlich founded Stanford's Center for Nature and Society in 1984 and has written more than 40 books and more than 1,100 scientific articles on ecology, the environment, and population dynamics. He is best known outside academia for the book The Population Bomb (1968), written with his wife, the biologist Anne H. Ehrlich, who survives him.

The book became a bestseller reprinted more than 20 times and translated into several languages. She predicted in stark terms that population growth would deplete the Earth's resources, leading to wars and social collapse.

Ultimately, the book popularized but also divided the US environmental movement.

The battle over Paul Ehrlich's book

“The Population Bomb” began with an explosive statement: “The battle to feed all mankind is lost.” And because “the stork has overtaken the plough,” as the Ehrlichs wrote, “hundreds of millions of people will starve.” Overpopulated India was doomed, they argued, and England “will no longer exist in the year 2000” following a major social and ecological collapse.

The Conversation notes that these drastic warnings, while exaggerated, at least seemed plausible at the time. Older researchers, including British chemist and author Charles Percy Snow and oceanographer Roger Revelle, had also warned that population was growing faster than food production.

The Ehrlichs were influenced by books such as “Road to Survival,” the 1948 bestseller by environmentalist William Vogt, and “Our Plundered Planet,” by paleontologist Henry Fairfield Osborn. All of these thinkers were considered successors to the original “Cassandra” of demographic catastrophe, the English economist Thomas Malthus. His seminal book “An Essay on the Principle of Population” warned as early as 1798 that the world's population would inevitably outstrip food production.

Even worse, Malthus predicted, efforts to produce more food will only perpetuate the cycle of hunger and poverty. However, new agricultural crops and modern techniques prevented the catastrophe predicted by Malthus in the 19th century. As a result, the term “Malthusian” has come to denote excessively pessimistic views of complex social problems.

Another type of Malthusian

Handsome and eloquent, Ehrlich captured the public's imagination through press articles, conferences and television appearances. “The Population Bomb” propelled him into the center of a heated global debate about the environment and conservation. He appeared more than 20 times as a guest on “The Tonight Show” with Johnny Carson in the 1970s and early 1980s.

This was not the typical public profile of a biology teacher. As New York Times reporter Robert Reinhold observed in 1969, Ehrlich was “representative, perhaps, of a new generation of scientists willing to engage in the unscientific and sometimes tough business of public activism against things like DDT, highway construction, and population growth.”

Obviously, not all environmentalists agreed with Ehrlich's idea that population was the primary threat. Barry Commoner, another leading biologist of the time, believed that faulty technology was the main source of environmental problems.

But Ehrlich and the physicist John Holdren, a longtime collaborator of his, saw technology and population as interdependent factors in a complex social problem, summarized by the equation I = P × A × T (Impact = Population × Affluence × Technology). In other words, population growth, the level of wealth, and the types of technologies used all contribute to human impact on the environment.

The debate between Ehrlich and Commoner confused some, but it highlighted two different approaches to environmental policy. In Commoner's view, technological problems such as toxic waste and nuclear radiation should be solved through cleanup and improved processes.

Ehrlich argued that reducing overconsumption and limiting population growth would also help alleviate these problems. To slow population growth, he proposed promoting contraception and expanding access to abortion, even extreme coercive methods such as forced sterilization.

By the 1970s, the emphasis on population growth had become widely accepted. The first United Nations Conference on the Human Environment, held in Stockholm in 1972, placed population growth, along with pollution and underdevelopment, among global priorities. Later that year, the Club of Rome echoed Ehrlich's warnings in its influential report Limits to Growth.

Scarcity or abundance?

Global population continued to grow in the 1970s and '80s, but the effects Ehrlich predicted did not occur. This was largely due to the Green Revolution, a broad campaign by governments and research institutes to provide high-yielding varieties of wheat and rice, pesticides and mechanized agriculture to developing countries. These tools increased harvests and drastically reduced the risk of famine.

Agronomist Norman Borlaug, one of the leaders of this effort, received the Nobel Peace Prize in 1970. In his acceptance speech, Borlaug emphasized that the Green Revolution was only a temporary respite and that limiting population growth remained essential in the fight against hunger.

Conservative economists and scientists were not convinced. An important critic, the economist Julian Simon, advocated what became known as the “cornucopian” view, according to which the only limits to growth are imagination and ingenuity. Simon argued that the Earth has an unlimited capacity to provide resources, and humans will constantly innovate to use them.

In 1980, Simon made a public bet with Ehrlich that the prices of five important industrial raw materials—copper, nickel, tungsten, chromium, and tin—would fall over the next decade. Ehrlich would have preferred an environmental measure, but he agreed, arguing that resources would become scarce and prices would rise.

Simon argued that markets and new technologies would drive down prices. In the end, although the prices of these metals had previously risen and would rise again in the 1990s, they fell between 1980 and 1990. Simon won the bet, and Ehrlich sent him a check in 1990 for $576.07 representing the price difference.

It is only a matter of time, argued the researcher until the end of his life

After the catastrophes predicted in “The Population Bomb” failed to materialize, many critics derided Ehrlich's positions. “As you've noticed, England still exists. And so does India,” quipped The New York Times columnist Clyde Haberman in 2015.

“Paul Ehrlich is a misanthrope who would make you apply for a government permit to have a child if he could,” Chelsea Follett of the libertarian-leaning Cato Institute wrote in 2023.

Ehrlich and his supporters responded that while the Green Revolution had delayed widespread starvation, the human impact on the planet had become increasingly pressing. Taking into account issues such as climate change and toxic pollution, Ehrlich claimed in 2009 that “The Population Bomb” had been “far too optimistic”.

In “Life,” his 2023 memoir, Ehrlich expressed deep gratitude for a 70-year career in science. However, he was frustrated by what he saw as the inability of science to penetrate the profoundly unscientific American political culture.

It also lamented that the environmental movement was failing to effectively oppose “the forces that pose existential threats to civilization.” He died on March 13 at the age of 93, according to a later announcement by his family.