In 1968 Paul R. Ehrlich dropped a bomb on a world happily in the midst of a decade of prosperity and economic growth. In his book The Population Bomb, this virtually unknown butterfly entomologist from Stanford University warned that overpopulation of the planet would lead in the following two decades to such food scarcity that it would cause the death of hundreds of millions of people in an unprecedented global collapse. More than half a century later, it is clear that while there is no shortage of problems afflicting humanity, it is also evident that the apocalypse of the population bomb did not materialise. However, with their mixture of gloom and hope, Ehrlich’s warnings still resonate loudly enough today to keep the debate alive.
The idea of the disparity between population and resources has a long history. At the end of the 18th century, the British writer Thomas Malthus shook the thinking of the Industrial Revolution with his book An Essay on the Principle of Population, in which he posed a problem that was difficult to solve: how to maintain a population that is increasing in geometric progression with food production rising in arithmetical progression? Malthus’ work sparked an intense debate not without fierce criticism, but also inspired the theory of natural selection by means of which Charles Darwin and Alfred Russel Wallace provided a driving force for biological evolution.
Population, Resources, and Environment
The debate over the Malthusian catastrophe continued until the 20th century, when the world’s population started to rise unchecked. At the end of the 1940s and during the 1950s, a neo-Malthusian trend began to emerge, bolstered by works such as Road to Survival by the ecologist and ornithologist William Vogt. It was Vogt’s book that first drew the attention of the young Ehrlich, then a university student, to the problem of overpopulation and limited planetary resources. In the mid-1960s, in a hotbed of new ideas about birth control and sterilization, Ehrlich, now a faculty member at Stanford, began to lecture on the topic of overpopulation, prompting the director of the environmental organization Sierra Club to suggest that he compile the content of his talks into a book.
In just three weeks, Ehrlich and his wife Anne—whose name was omitted because the editor preferred a single author, something Ehrlich later regretted—hastily wrote a manuscript entitled Population, Resources, and Environment. This was not punchy enough, so the editor changed it to The Population Bomb, taking the title from a pamphlet published in 1954 by businessman Hugh Moore. The first sentence of the prologue to the Ehrlichs’ book got straight to the point: “The battle to feed all of humanity is over. In the 1970s hundreds of millions of people will starve to death in spite of any crash programs embarked upon now.”
At first, the Ehrlichs’ population bomb had little impact, until the biologist’s appearance on The Tonight Show with Johnny Carson multiplied its shockwave; within three years the book was a bestseller and became one of the most influential and controversial essays of the 20th century. But while the debate continued, the 1970s and 1980s passed, and while the world was never short of crises and conflicts, the great global famine predicted by Ehrlich never came to pass.
Of course, some regions of the world suffered from the scourge of hunger. But as critics of the book pointed out, the cause was never a problem of actual food shortages, but one of political instability and corruption. At the same time, anxiety about overpopulation sparked a wave of radical thinking that revitalised opinions such as the defence of eugenics and inspired policies denounced as being contrary to human rights, including forced sterilisations or China’s one-child policy.
The bomb is still ticking
However, while opponents of the population bomb thesis declared Ehrlich’s predictions to be flawed, the biologist has repeatedly stated that his book did not contain such predictions, but rather scenarios. And a scenario changes when its premises change; world population growth has slowed considerably since the 1960s, from 2.09% in 1968 to 1.05% in 2020. As Ehrlich tells OpenMind, this has been one of the factors that have averted the crisis of global famine, along with technological progress and the so-called Green Revolution in agriculture, as well as, perhaps, the effect of the self-fulfilling prophecy when a dystopian prediction galvanises efforts against its materialisation. But Ehrlich still sees the spectre of famine: “The levels of hunger, and especially micronutrient malnutrition, are disgustingly high,” he says. For the author of the population bomb, the situation since the 1960s has not only not improved, but today is “much more dire.”
Today the debate continues but no consensus has been reached. Some academics and scientists believe that the population bomb is still ticking and that it deserves a new and more balanced interpretation, pointing out that the drop in the birth rate can be a lever for development in countless countries; nevertheless, many voices concur that the problem is not so much the total size of the population, but rather over-consumption and inequality in the distribution of resources. On the opposite front, the advocates of unbridled growth continue to dismiss Ehrlich and his arguments. But this discussion is often, and perhaps inevitably, tinged with political overtones.
One thing in particular is clear, the environmental problem is more pressing today than it was at the time of the book’s publication. Pandemics aside, climate change has become a top global priority. “When the bomb was written, rapid loss of biodiversity and toxification of the planet were unknown,” says Ehrlich. Today the biologist is engaged in the task of studying and publicising the so-called Sixth Extinction, the mass disappearance of species from the planet which, unlike the five major ones in prehistoric times, is mainly caused by human beings. “Time to act is now very short,” he warns.