The most crucial evidence is that the Doomsday Empire imposed extremely strict restrictions on the fertility of the people.

In fact, this is also the landmark event of the Doomsday Empire's domination of the United Continent.

Five hundred years ago, the Doomsday Empire officially introduced a policy of restricting births on the grounds of "improving the capabilities of human beings themselves and improving the population structure of human beings".

At that time, there were about three billion people on the United Continent.

Theoretically, if the protection of the natural environment is not considered, and the living space for other living beings is not considered, after the energy problem is completely solved, at least 100 billion people can be accommodated on the United Continent. However, this is only theoretical data, and it is impossible to reach this scale in practice.

How much time does it take to go from 3 billion to 100 billion?

Theoretically, it will take less than a hundred years.

Human beings are also living beings, and living beings have two natural instincts, one is to survive and the other is to reproduce. Under the condition that the means of subsistence are sufficiently guaranteed, especially when machines replace people and engage in most of the productive social labor, even ordinary people, without participating in labor, can obtain sufficient means of subsistence, and everyone has the urge to reproduce, and it is an instinctive impulse that is difficult to suppress through reason. If we take twenty years as a generation, and the number of each generation doubles, then in a hundred years the population will increase thirty-two times. Taking into account the fact that scientific and technological advances have increased the average life expectancy of human beings, the actual number of people will increase by sixty-three times.

That is, it will only take about eighty years for the population to grow from three billion to 100 billion.

Obviously, if left unchecked, the limited living space on the United Continent will become a new "resource" and an object of contention for all.

No matter how powerful the Doomsday Empire is, it can't create more space.

The only way to avoid a catastrophe is birth control.

This is not a matter of planning, but of total control.

It's just that, in the beginning, no one recognized this at all. About fifty years later, the common people on the United Continent found that they had lost their reproductive rights, and the power to produce offspring was in the hands of the Empire, and it became a key bargaining chip for the Empire to control the common people.

That is, all those who have undergone "eugenic modifications" have lost their natural fertility!

To put it simply, procreation is no longer a normal physiological function of human beings, but has become a scientific and technological means, a technique mastered by rulers. That is, all people have a corresponding genetic profile at birth. In order to have children, fertility indicators must be obtained from the Imperial government, and then the Imperial "Academy of Future Sciences" will start to combine the genetic samples preserved by both parents and then breed offspring by artificial cloning.

For the first 150 years, many people could not accept this way of having offspring.

For this reason, there have even been some rebellions.

It is a pity that the spontaneous resistance of the populace is very weak in the face of the powerful institutions of the empire, and not everyone is willing to give everything for it.

The sporadic rebellions lasted for a hundred and fifty years, and were finally defused by an invisible force.

That is, the new human beings born through the "eugenics project" have the excellent genes of both parents, not only are they stronger and smarter, but also have a higher chance of gaining superpowers, so that when they grow up, they have a greater chance than their peers who have been born through natural childbearing.

It was precisely because of this that the people of the United Continent gradually agreed with the approach of the imperial authorities.

Of course, this is also related to some of the policies of the imperial authorities. For example, artificial cloning is replaced by pregnancy, in which a fertilized egg is implanted into the mother's womb, so that the mother can give birth to offspring by pregnancy, rather than producing offspring entirely through cloning, as was the case in the first place.

All in all, after all the turmoil, there are no more naturally fertile people on the United Continent.

On the other hand, for the common people on the United Continent, giving birth to offspring is a very luxury, and even the dream of many people.

The point is, fertility indicators are becoming fewer and more expensive.

In the big cities of the central region, one fertility indicator is equivalent to 20 years of savings of both parents. According to Memphis, in his grandfather's generation, fertility was very cheap, with most couples able to raise three or four children, and some even five. In his father's generation, most couples could only raise three children, and very few were able to raise four children. Memphis was an exception, as he followed his father to the northern desert region and was able to receive additional compensation from the government. In the big cities of the central region, many couples may not be able to achieve a fertility indicator throughout their lives.

According to information provided by Memphis, the total population of the United Continent is less than 20 billion.

Of course, this is already a very staggering number.

Most of the people live in cities in the Midlands, and the cities are very large, such as Doomsday City, the capital of the Empire, which has about two billion inhabitants. What is this concept? The area of Doomsday City is about 10,000 square kilometers, which is equivalent to 200,000 people per square kilometer of land, and each person is only five square meters! After deducting infrastructure such as streets, everyone's living space is even narrower.

Of course, according to Memphis, Doomsday City is a city of high-rise buildings, almost built in the sky, its tallest building is more than two thousand meters high, most of the other buildings are more than a thousand meters high, and the underground part of the city is also fully utilized. The production facilities related to life, including the factories that produce food, are all located underground, and the above-ground parts are residential and commercial areas, and the traffic of the city is completely three-dimensional, there are almost no surface streets, and most of the streets are located inside the buildings, mainly in the commercial area. The comprehensive three-dimensional development allows everyone to obtain enough living space.

It's just that these are secondary issues.

The point is, what does the Doomsday Empire want to do to control births.

There is only one answer, that is, the rulers of the Doomsday Empire have long known that the United Continent is not the only World Continent, and there is a broader World Continent outside, but there is no way to break through the powerful barrier that imprisons the United Continent, and it is impossible to develop into a broader space.

Obviously, the empire can only survive by controlling the number of people.

It's just that all that changed four years ago.

That is, four years ago, the authorities of the Doomsday Empire suddenly announced that they would gradually relax the birth restrictions, and the plan was to allow all couples to raise two children after five years.

It's just that when Memphis talks about this matter, it doesn't mention the church, it doesn't mention foreign invasions, and it doesn't mention the outside world.

At that time, no one connected the new policies announced by the imperial authorities with the outside world.

In fact, after hundreds of years, few people have thought about the outer world, and almost all the common people believe that the space they are in is the United Continent, and there is nothing outside the United Continent, and no one is willing to risk exploring the outside world.

Of course, that doesn't mean you can keep secrets alive forever.

About three years ago, the people of the United Continent gradually realized that there was an extremely vast world realm outside.

That is, the arrival of the first batch of smugglers has allowed more people to discover the secrets that have been hidden by the imperial authorities, and also realize why the imperial authorities want to restrict births.

It's just that, for most people, this is not necessarily a good thing.

As there was more and more awareness of the outside world, there was a commotion within the empire, and the common people also put forward more demands on the imperial authorities, such as sending troops to explore the outside world, to open up colonies, and even open the right to establish overseas colonies to the common people.

Thankfully, this is only three years.

During these three years, the Imperial authorities have been making concessions to the common people, and gradually meeting their demands, such as sending troops to explore the outer world, and promising to give everyone the opportunity to explore the colonies once they decide to establish overseas colonies.

It is precisely in this way that the empire has been maintained.

For the vast majority of civilians, the promises of the imperial authorities were sufficient. In any case, for people who already live more than 140 years old, waiting a few more years is not a problem at all. Besides, not everyone advocated the creation of overseas colonies.

If there is no serious upheaval, this situation will be maintained, and after a year, all parents will be able to obtain the indicator of having two children.

The problem is that the upheaval of half a year ago has changed all that.

Memphis also didn't say anything about what happened half a year ago, or he couldn't explain it at all, all he could say was gossip from other fugitives.

There is only one key message, the empire does not exist!

Of course, the Empire didn't exist anymore, and the other fugitives didn't make it clear.

Only one thing is certain, the empire has lost control, and power has fallen into the hands of those in power, especially those generals who control the army. Worse still, these people in power seem unwilling to share power with anyone else, or to rebuild a new empire, and then war breaks out over resources, for land, for population, for everything that no one has valued before.

It was a sudden war.

For ordinary people who are not prepared at all, or even mentally prepared, this is a disaster that has not been encountered in hundreds of years.

Ordinary civilians like Memphis can only do everything they can to survive.

Of course, others are no exception, and perhaps no one is exceptional, and so are those in power.