By Fumihiko Takeda

Part I

The Question the World Should Ask

For many years, governments around the world have regarded population decline as one of their greatest national challenges. Declining birth rates are widely viewed as threats to economic growth, labor markets, pension systems, national security, and even the long-term survival of nations. Consequently, many governments have introduced policies designed to increase the number of births.

Before asking how to increase the population, however, we should first ask a more fundamental question.

Is population decline itself really the problem?

Or is the real problem that we continue to judge the twenty-first century by standards that belonged to the twentieth?

For centuries, a large population often meant a strong nation. Agriculture depended on human labor. Industrialization required factories filled with workers. Larger populations created larger markets and larger armies. Under such conditions, population growth naturally became one of the principal indicators of national strength.

But history has not stood still.

Humanity has entered a new era. Artificial intelligence, robotics, biotechnology, and advanced science are rapidly transforming the relationship between population and prosperity. The strength of a nation will increasingly depend not on the number of its people, but on how effectively its people create and apply knowledge, science, and technology.

This transformation compels us to reconsider one of the most widely accepted assumptions in modern politics.

Does every nation really need a larger population?

Japan is one of the first major countries to experience long-term population decline, yet it remains one of the world's leading technological powers. Many observers regard this only as a crisis. I believe they are looking in the wrong direction.

Japan may become the first major nation to demonstrate that a society can remain prosperous, secure, and innovative even while its population declines. If Japan succeeds, its experience will be valuable far beyond its own borders. Many advanced nations are already experiencing declining birth rates. Sooner or later, they will confront the same challenge.

For that reason, this is not simply Japan's issue.

It is a question about the future of human civilization.

There is, however, an even more fundamental question.

How many people should live on the Earth?

This question is rarely discussed. Political debate usually begins with the assumption that a larger population is always desirable. I believe that assumption deserves careful reconsideration.

The Earth possesses limited land, limited fresh water, limited forests, limited energy resources, and limited ecological capacity. Every additional person requires food, water, housing, transportation, energy, and countless other resources. As the world's population grows, pressure on the natural environment inevitably increases.

The destruction of the Amazon rainforest, the loss of Indonesia's tropical forests, the depletion of freshwater resources, and the continuing decline of biodiversity all have multiple causes. Yet behind these problems lies an undeniable reality: as the human population expands, so does the scale of human activity.

Efforts to reduce pollution, recycle waste, and develop cleaner technologies are essential and must continue. But unless humanity also asks what level of population allows both people and nature to flourish together, we will continue treating symptoms while ignoring one of the underlying causes.

Therefore, the question is not simply how many people the Earth can sustain.

The more important question is this:

How many people can live healthy, peaceful, and prosperous lives while preserving the natural environment for future generations?

I believe this is one of the defining questions of the twenty-first century.

Chapter 1  The Question the World Should Ask

Population Is Not the Source of National Strength

If continuous population growth is not always the answer, what should become the true foundation of national strength?

I believe the answer is clear.

In the twenty-first century, the strength of a nation will depend increasingly not on the size of its population, but on the quality of its people.

This is not merely a philosophical observation. It is already becoming an economic reality.

Artificial intelligence now performs many tasks that once required human labor. Robotics is transforming manufacturing, logistics, agriculture, and medicine. Scientific innovation is replacing physical labor with knowledge. Economic value is increasingly created by ideas rather than by the sheer number of workers.

This does not diminish the importance of human beings.

On the contrary, it makes education, scientific capability, creativity, and technological innovation more important than ever before.

A single outstanding engineer may develop a technology that improves the lives of millions of people. A single scientific discovery may contribute more to humanity than the labor of thousands. Knowledge has become one of the world's most valuable resources.

Japan is particularly well positioned to understand this transformation. It possesses few natural resources, imports much of its energy, and maintains a relatively low level of food self-sufficiency. These structural realities cannot simply be ignored.

For that reason, population growth should not automatically be regarded as a national objective. Every additional citizen requires food, water, energy, housing, transportation, education, medical care, and many other public resources. Unless productivity rises even more rapidly, a larger population also means greater dependence on imported resources.

The more important challenge is therefore not how to support more people.

It is how to enable every individual to contribute more through knowledge, science, and technology.

National investment should therefore focus on those fields that strengthen human capability: education, scientific research, artificial intelligence, robotics, biotechnology, advanced agriculture, and clean energy.

These investments can increase national strength without requiring unlimited population growth. More importantly, they improve the quality of life for future generations.

The purpose of national policy should not simply be to produce more people. It should be to help every individual develop his or her full potential.

History demonstrates that civilizations do not become great simply because they become larger. They become great because they create new knowledge, new technologies, and new ways to improve human life.

The twenty-first century should therefore become an age in which nations compete not by the size of their populations, but by the power of human intelligence.

That transformation has already begun.

The nations that recognize it first may well become the leaders of the next era.

Chapter 2   The Earth Has Limits

Discussions about population are often framed primarily as economic issues. I believe they raise a far more fundamental question—the future relationship between humanity and the Earth.

The Earth is not an infinite system. Forests, rivers, farmland, fresh water, fisheries, mineral resources, and ecosystems are all finite. Technology can improve efficiency, reduce waste, and create cleaner sources of energy. These advances are indispensable.

But no technology can make a finite planet infinite.

As population grows, so does the demand for food, water, housing, transportation, and energy. At the same time, pressure on forests, rivers, oceans, wildlife, and natural ecosystems inevitably increases.

This does not mean that every environmental problem is caused solely by population growth. Consumption patterns, wasteful lifestyles, poor public policy, and unsustainable economic practices also play important roles.

Nevertheless, one fact cannot be ignored.

As the human population increases, the overall pressure placed upon the Earth's ecosystems also increases.

We already witness this reality around the world. Vast areas of the Amazon rainforest continue to disappear. Tropical forests in Indonesia have been cleared on a massive scale. Agriculture, mining, logging, and commercial development all contribute to these changes.

Yet behind these individual causes lies a common reality: human civilization requires land, food, energy, water, and raw materials.

For many years, environmental policy has focused primarily on reducing pollution through cleaner industries, better recycling, and renewable energy. These efforts are both necessary and valuable, and they should continue.

However, they do not answer a more fundamental question.

How many people can the Earth support while allowing both humanity and nature to flourish together?

Simply keeping people alive is not enough. Human beings should be able to enjoy healthy, peaceful, and prosperous lives. Future generations should inherit clean air, clean water, fertile land, rich biodiversity, and healthy ecosystems.

Environmental policy should therefore pursue a broader objective.

Its goal should not be economic growth alone.

Nor should it be unlimited population growth.

Its ultimate goal should be a sustainable balance between human civilization and the natural world.

Without such balance, competition for food, water, energy, and land will inevitably intensify. History repeatedly demonstrates that scarcity of essential resources often becomes a source of conflict.

A wiser civilization should reduce such pressures before they become crises.

For this reason, I believe humanity should begin an open international discussion about the Earth's long-term sustainable population.

This is not a call for coercion.

It is not an argument that governments should determine how many children families may have.

It is simply an invitation to recognize an unavoidable reality:

Unlimited population growth cannot continue forever on a finite planet.

Ignoring this question will not make it disappear.

Addressing it honestly may become one of humanity's greatest responsibilities in the twenty-first century.

Chapter 3   A New Direction for Human Civilization

This essay is not intended to praise population decline itself.

Nor does it argue that governments should determine how many children their citizens should have. The decision to have children must always remain a matter of individual freedom.

The question I wish to raise is more fundamental.

What kind of civilization should humanity seek in the twenty-first century?

For centuries, many nations believed that a larger population naturally produced greater wealth and greater national power.

That belief belonged to the agricultural and industrial ages.

Today humanity is entering a different era.

Artificial intelligence, robotics, biotechnology, and scientific innovation are rapidly transforming society. In this new age, national prosperity and strength will depend less upon the number of people and increasingly upon the knowledge, creativity, scientific achievement, and technological capability of each individual.

At the same time, the Earth remains finite.

Its forests, fresh water, farmland, energy resources, and ecosystems all have limits.

Reducing pollution remains essential.

Developing cleaner technologies remains essential.

But these efforts alone cannot solve the deeper challenge facing humanity.

We must ask not only,

"How many people can the Earth support?"

We must also ask,

"How many people can live healthy, peaceful, and prosperous lives while preserving the Earth for future generations?"

I believe this is one of the defining questions of the twenty-first century.

Japan is among the first nations to confront this challenge.

For precisely that reason, Japan should not regard population decline only as a crisis.

Instead, Japan has an opportunity to demonstrate that a nation can remain prosperous, secure, scientifically advanced, and environmentally sustainable even while its population gradually declines.

If Japan succeeds, it may offer a new model of civilization for the rest of the world.

The twenty-first century should not become an age in which nations compete simply to increase their populations.

It should become an age in which nations compete to create societies where both humanity and nature can flourish together.

The true measure of national strength will increasingly be found not in the quantity of people, but in the quality of human knowledge, science, creativity, education, and technological innovation.

I call this new direction of civilization Brainism.

Brainism is the belief that the future of nations and of humanity will be determined not primarily by the size of their populations, but by the power of the human brain. In the twenty-first century, knowledge, science, technology, creativity, and education will become the true foundations of national prosperity, human progress, and the sustainable future of civilization.

Fumihiko Takeda is the founder and Representative of the Lincoln Club, an independent political and policy research organization that he established in Japan on November 19, 1993. The Lincoln Club is his own organization and is not affiliated with, or a branch of, any organization in the United States.

In 1974, he founded the Cooperative Center, an information service company that conducted research and analysis for Japanese government agencies and major newspapers. In 1977, he established the Institute for Ultimate Democracy and has since devoted his career to the study of democracy, constitutional reform, electoral systems, and institutional design.

From 2006 to 2014, he served as a lecturer at the Graduate School of Law, Keio University. He is the author of numerous books and articles on democratic governance and political reform, including works on direct democracy, constitutional issues, and election systems. His policy proposals have been discussed in major Japanese publications and public policy forums.