Beyond the Age of Growth

An Interview with Ugo Bardi

The transcript of an interview I gave to the COR Magazine 3 July 26, by Neda Lukic about my new book “The End of Population Growth”

Professor Ugo Bardi, Scientist, Author and Member of The Club of Rome

3 July 2026

As fertility declines and resource constraints intensify, humanity faces a historic transition that challenges many of the assumptions upon which modern economies and societies have been built

Professor Ugo Bardi, scientist, author and member of The Club of Rome, visited Belgrade in early June to present his latest book, The End of Population Growth: Reaching Humankind’s Planetary Limits. Published as a report to The Club of Rome, the book revisits one of the central questions raised by the landmark 1972 report The Limits to Growth: can economic and population growth continue indefinitely on a finite planet?

Drawing on decades of research into complex systems, demographic trends and environmental constraints, Bardi argues that humanity is entering a new phase defined not by expansion, but by adaptation to ecological realities.

Professor Bardi, your new book, The End of Population Growth, suggests that humanity may be entering a fundamentally different era. Is the end of population growth primarily a demographic phenomenon, or a symptom of deeper economic, ecological and civilisational limits?

The book examines the current situation by seeing humankind as a complex system reacting to a perturbation caused by having reached our physical limits on Earth. Global warming, resource depletion, pollution and other factors lie at the root of this trend.

The challenges we face are deeply interconnected and cannot be solved by addressing individual problems in isolation

Then, at the individual level, the perception of overcrowding and the loss of future perspectives causes people to decide that they don’t want children, or that they want small families. But that’s not the only factor, and perhaps not even the most important. Chemical pollution is also affecting the human reproductive system, causing a measurable decline in fertility. Other factors are pushing in the same direction: stress, the declining quality of the diet, the widespread use of drugs, and more. Warming has also been shown to have a negative effect on fertility. There is no single cause for the epochal reversal of the past growth trends.

For more than two centuries, modern societies have been built on the assumption of continuous growth. What are the likely consequences if both population growth and economic growth begin to slow simultaneously?

The classical school of economists, developed about two centuries ago, was not focused on growth, but saw the economy as tending to reach stability. It was only in relatively recent times, after World War II, that “growth” became the widespread totem that all economists revered. Understandably, because the great economic expansion that took place in the West after the war appeared, for a while, to be the natural state of things.

But it is a basic law of nature that when something cannot last forever, eventually it will have to stop. It is happening. It is not so different from what happens when you climb a mountain. The old Zen koan tells you to keep climbing, but in the real world this is a little difficult. So, you have to walk down.

The consequences depend only on how steep the path is: if it is not too steep, it is a pleasant walk. If it is too steep, it is a fall, and someone may get hurt. This is the main point I try to make in my book.

Throughout your work, you connect declining fertility, pollution, biodiversity loss and climate change. Should these be viewed as separate challenges, or as different manifestations of a single systemic crisis?

As I mentioned in response to Question 1, this is the central point of an analysis based on 50 years of work by The Club of Rome. In a complex system, there are no single causes and effects. There are only forcings and feedbacks.

To explain, think of a typical complex system: a cat. Its behavior is approximately predictable, and you know what happens when you shake the box with the kitty treats. But if you pet a cat you don’t know, you can’t predict whether it will purr in happiness, or turn around and bite you. This is the essence of the science of complex systems.

The problems we are seeing in front of us are all connected, and cannot be solved acting on single ones.

In your work, collapse is often presented not as a failure of a system, but as a natural consequence of accumulated stresses and the laws of thermodynamics. If environmental pollution also affects human health, fertility and cognitive performance, could it be weakening society’s capacity to recognise and manage the very risks that threaten its long-term stability?

The universe changes not along smooth lines, but through cycles of growth and decline. If we can recognise what we are facing and manage it well, it may even be a slow and relatively gentle decline. If we don’t, it will not be pleasant at all. But the final result doesn’t change so much.

Population decline is deeply embedded in the structure of modern societies, and it is extremely difficult to reverse a trend of fertility decline that has been ongoing for decades almost everywhere

We’ll go down for a while, and then come back. Maybe there is a stable future after this cycle, but nothing lasts forever.

If you were advising today’s political and business leaders, what is the one assumption about the future that they should abandon, and what is the one principle they should embrace in order to build more resilient societies?

Tolstoy is reported to have said that “a king is a slave of history.” It means that leaders don’t have much more decisional power than we, humble commoners, do. So, advising leaders is as effective as stopping a tsunami with a teaspoon.

Change does not occur because leaders want it. They normally see their business as exactly the opposite: stopping change as much as they can. Revolutions are started when someone thinks that it is time to put a good idea into practice. It doesn’t work every time, but trying new ideas is the way we move toward the future. And we must move in that direction, no matter whether we like it or not.