Isaac Asimov - The End (an article from the XNUMXs fearing a population explosion)

The article was originally written in 1970 and published in Fantasy 2000, Issue 12, 1981

Among my other occupations, I am also a professional prophet, this means, I am paid to predict the future. There is a catch in this of course: since I do not mislead the readers, there is a sharp and clear limit to my ability. Since I don't look into crystal balls, I have no messengers from their hidden owner, I lack any talent for experiencing divine revelation and am completely devoid of mystical intuition, then I have no power to tell someone which horse will win the race, or if his wife is going to cheat on him, or how long he will live.

All I can do is observe the world as continuously as possible (a rather difficult task these days), try to assess what is happening, and then make the basic assumption that whatever is happening will continue to happen. Having made this assumption, I can make very limited predictions. I can tell you, for example, when the horse races will stop altogether, when it won't matter that someone's wife cheats on him, and above all - how long we will all (apart from perhaps insignificant exceptions) live longer.

For example, I look at the world today and see people, masses of people. Regarding these masses of people two things can be said.
1) There are more people today than there have ever been at any time;
2) The number of people is increasing at a faster rate than at any other time in history.

Just as an example - in the days of Julius Caesar, the total number of humans on Earth was probably something like 150 million, and the world's population grew at a rate of 0.07 percent per year (about one hundred thousand people per year). Today the world's population is estimated at four billion, or more than 24 times the population in the days of Julius Caesar. And today's population grows at a rate of 2 percent every year - 30 times the growth in ancient times. Today, 70 million people are added to the earth every year, that is, every two years an amount of people equal to the entire population of the world in the glorious days of Rumi is added to our world.

The question is what does this mean for the future?

Doom seers, among whom I am one, cry 'doom', the optimists, on the other hand, talk about modern science, the improvement of agriculture, the desalination of ocean water, nuclear fusion energy, and the settlement of other planets. And really, why not? Let's accept everything the optimists say and look at some numbers.

If we accept the number of about four billion as the world's population today, and assume that the average weight of a human being is about fifty kilograms (there are small people, and there are children), then the total mass of human flesh and blood reaches about 180 million tons, more or less. It is estimated that the number of people on earth (and therefore also the total mass of human flesh and blood) increases so that it doubles every 35 years. If so, allow me to present you with a mathematical equation - not because any of you particularly need it, but because without it I will be accused of pulling numbers out of a hat.

This equation will give us the number of years X needed to reach a mass of human flesh and blood equal to Y, if we start from the population that exists today and multiply it every 35 years. To make it easier to handle the equation, we will extract X from it and get
X=115(log Y-8.25)
Based on the second equation we can ask ourselves the following question: how many years are required for us to multiply until the total mass of humanity equals the total mass of the universe?

I present this equation because I suspect that no optimist would be willing to argue that man can reach this point, so this constitutes an impeccable upper limit. It is possible, of course, that the time needed to reach this fantastic end is so long (trillions of years, you might think?) that there is no point in discussing it. Well, let's see…

The universe includes (roughly estimated) 100 billion galaxies, each of which has about 100 billion Saturnian stars similar in size to our Sun, on average. The mass of the sun is approximately 2.2 billion billion tons, and hence the mass of the entire known universe in tons (plus some mass to take into account planets, interstellar dust, etc.) comes to the number 3 followed by 50 zeros or 3 times ten to the power of 50 in the mathematical formulation.) If We will place this number in place of Y in equation number 2 and we will get that logy=50.48. We subtract 8.25 from this and multiply the difference by 115, we find that X is equal to 4,856.

If so, at the current growth rate of the entire human population, the mass of all humanity will equal the mass of the known universe in 4,856 years. In 6826 we will reach the absolute end.

A period of 4856 years is long, of course, compared to an individual's life. But if the length of time until our lives are cut short is so short compared to the trillions of years we thought about before, then we should be bothered by the feeling that the real limit will come even sooner. After all, even the staunchest optimist would not imagine that we would have enough to settle all the planets of all the Saturn stars of all the galaxies and every nest to convert the stars themselves into food within the next few thousand years.

In fact, it is almost certain that during this period we are destined to be confined to planet Earth. Even if we colonize the rest of the solar system there is no hope that we will be able to transfer significant parts of the human population to 'forbidden' worlds such as the moon or Mars. Therefore, let us ask ourselves how long it will take humanity (at the current rate of multiplication) to reach a mass equal to that of our own planet. The mass of the Earth is 6,600 billion billion tons and if we take this number as Y, then logy=21.82. If we put this in the equation we find that X is equal to 1,560.

In 1,560 years, at the current rate of reproduction, that is, in the year 3530, the mass of humanity will equal the mass of the Earth. Will there be an optimist among the audience who will raise his hand if he believes that humanity can achieve this under any circumstances?

Let us seek, then, a more real limit. The total mass of all living tissue is currently estimated at something like 20 million million tons. , and this number cannot really increase as long as the fundamental source of energy for life is sunlight. Only a limited amount of sunlight reaches the earth; Only this amount of light can be utilized for the photosynthesis process; Therefore, only a limited amount of living plant tissue can be built each year. The amount created is balanced by the amount destroyed each year, either by natural death or as a result of being eaten by animals.

The animal world is roughly estimated as one-tenth of the mass of the plant world, which means approximately two million million tons in the entire world. This mass cannot grow either, since if for some reason the contained mass of the animal world increases significantly, then the mass of plants will have to be eaten faster than it can be regenerated. As long as the sunlight is just what it is, the food supply will be drastically reduced, and the animals will starve enough to restore their numbers to the correct level.

In fact, the total mass of humans has been increasing throughout history, but only at the expense of other forms of animal life. Every additional ton of humanity necessarily meant one less ton of non-human life.

Furthermore, as the number of human beings increases, it is necessary to grow a larger mass of plants for human consumption (either directly or to feed animals destined for the slaughterhouse), or for other purposes (clothing, for example). As the mass of seeds, fruits, vegetables and fibers grown for these purposes increases, the mass of other plants on earth decreases.

If so, let's ask ourselves how many years will pass until man multiplies, so that the mass of all mankind will be equal to the current mass of the entire animal world? Note that when this happens, there won't be any animals left that are. Neither elephants nor lions, neither cows nor horses, neither dogs nor cats, neither mice nor rats, neither fish nor crabs, neither flies nor fleas.

In addition to this, to feed all this human mass, the whole present mass of plant life must be in a form fit for human consumption; This means no more shade trees, no more grass, and no ornamental flowers. We couldn't afford fruit or nuts, because the wood is inedible. Even grains of grain would be uneconomical, because what would we do with the stalks? We will almost certainly have to feed only on plants that are completely edible and require only sunlight and inorganic materials to grow quickly - and these are the single-celled plants called algae.
Well, if the total mass of the animal world is two million million tons, logy equals 12.3 and X comes out to be 466.

In 2436, the number of people on Earth will be 40 trillion, or 10,000 times the number today (of course, the figure is correct for 1970). The total area of ​​the earth is approximately 540 million square kilometers. That is, in 2436 the average population density will be: approximately 74 thousand people per square meter.

Compare this number with the current population density in Manhattan at noon, which is around 37 people per square meter. In the year 2436 AD, even if humanity were to spread uniformly over all regions of the world - Greenland, the Himalayas, the Sahara Desert, Antarctica - the population density everywhere would be twice that of Manhattan today.

Imagine in your mind a huge world-wide complex of high-rise buildings (both on land and at sea), used for residences, offices, and industry. The roof of this entire complex will be entirely dedicated to algae tanks containing literally an ocean of water and 20 million million tons of algae in it. At regular intervals there will be pipes where the water will flow and separate from the algae; while drying the seaweed and processing it into food; The water will be returned to the tanks above. Other pipes lead up, will flow into the tanks the raw materials necessary to grow the algae, and which consist (what if not this?) of human excrement and finely chopped human corpses.

Even this limit, which is quite modest compared to our previous hypotheses, where we allowed the human race to multiply until its mass equals the mass of the universe or the mass of the Earth alone, is quite intolerable. Where can we find an optimist who believes that in four and a half centuries we can build a planetary volume twice as densely populated as Manhattan?

In truth, all of this is based on the assumption that the human population will continue to grow at its current rate, without limit. Obviously that won't happen. Something will happen to slow down the reproduction, stop it altogether, or even reverse its direction and reduce the population. The only question is what that 'something' will be.

It is clear that the surest way to accomplish this is a worldwide program for voluntary birth control; When all mankind enthusiastically takes up the matter. If this is not successful, the same result will inevitably be achieved by increasing the death rate - as a result of starvation for example. The question is: how much time do we have to convince the inhabitants of the planet to limit their births?

It is clear to everyone that universal birth control will not be easily achieved. There are stumbling blocks. There are important religious bodies that strongly oppose the use of sex for pleasure instead of fertilization and reproduction. There are entrenched social traditions that involve having many children with strong national security, with help at home and in the field, with security for old age. There are age-old psychological factors that link multiple children to the demonstration of male power and female duty.
There are new nationalist factors that cause minority groups to see birth control as a means to limit their numbers, and to see unlimited births as a method to take over the establishment.

So how much time do we have to deal with all of these?

If the problem were only born, we could argue that even if the situation continues exactly as it is today, science will ensure our existence for the next 466 years, until man is the only animal on earth.

Take energy, for example. Humanity uses energy at an ever-increasing rate, since the dawn of its existence. In part, this reflects the constant increase in population; but partly reflects the progress of the level of human technology. The discovery of fire, the development of metalworking, the invention of the steam engine, the internal combustion engine, the electric generator - all of these mean a sharp increase in energy consumption, far beyond the amount that could be attributed to the increase in population alone. Today, the rate of energy consumption by the human race doubles every 15 years, and we are entitled to ask a reasonable question - how long can this continue?

Today, many experts estimate that humanity consumes energy at the rate of 20 billion billion calories per year. To avoid dealing with too many zeros, we can define this quantity as an 'annual energy unit' (YU). In other words, we can say that today humanity consumes energy at the rate of 1 year per year. Assuming that the amount of energy consumed doubles every 15 years and with the help of an equation similar to equation M. 2, you can calculate the degree of energy consumption in any given year, and the total amount consumed up to that year.

Today, the lion's share of our energy comes from burning fuels (coal, oil and gas), which were gradually formed in the depths of the earth over hundreds of millions of years. There is a fixed amount of these materials, and they cannot be regenerated in a reasonable amount of time. The total amount of the fuel materials hidden in the belly of the earth will provide for its burning approximately 7,500 ya's. Not all of this amount will be able to be extracted from the depths. Some of it lies so deep, or is so diffused, that more arangia must be expended to obtain it than that to be extracted from it. It can be estimated that the energy produced from the obtainable fuel materials is more or less 1,000 ya's.

If those 1,000 ya's are all the energy sources we will have, then, at the current growth rate of energy consumption, the stock will run out completely in 135 years, that is, in the year 2,105. If we assume that those reserves of fuel materials that are not obtainable today, will be obtainable in the next century, this will give us about 45 more years, that is, we will have enough fuel until the year 2,150.

Of course, we don't have to use only fuels from the earth. Energy can be produced from nuclear fission of uranium and thorium. It is clear exactly how much energy can be produced from the available fissile materials, but this amount may be 100 times greater than that of the fossil fuels, and this will give us 135 more years and bring us to the year 2285.

In other words, in 315 years, one hundred and fifty years before we reach the ridiculous limit where humanity is the only life form, we will be completely depleted of all the main sources of energy we use today - assuming things continue to unfold as they are today.
Are there other sources?

There is solar radiation, which supplies the earth with 60 ya's per year, but we will need these for the algae tanks. There is nuclear fusion energy produced by turning the heavy hydrogen atoms (deuterium) in the oceans into helium. If all the deuterium in the oceans melts, the amount of energy that will be released from this will reach 500 billion yahs, which is enough for us to continue to exist comfortably, even at an accelerated rate of reproduction, even well beyond the time limit of a planetary oxygen density twice that of Manhattan. (There will be a problem of what to do with all the heat that will develop - thermal pollution - but there are also concerns that precede this).

Energy will not be a real limitation for humanity, if indeed we can produce controlled nuclear fusion energy in massive quantities. So far we have not done so, but we are on the way and probably will eventually. Now the question is: how much time do we have to make nuclear fusion possible, practical and massive?

We must do this before the stock of fossil fuels runs out and fission, of course, means that we have at most 315 years (unless we manage to limit population growth and energy consumption by then).

That sounds like enough time, but please wait a moment. The utilization of energy is inevitably accompanied by pollution, and the damage to the environment due to the rate of pollution that doubles every 15 years may precede the limit, much earlier than that determined by the disappearance of the energy sources.

But we only want to discuss the inevitable. Let's say we can get the infection under control. Suppose we overcome the effluents of the chemical industries, monitor the smoke, eliminate the sulfur in the smoke and the lead in the gasoline, use biodegradable plastic materials, turn garbage into fertilizers and a material source as well. What then? Is there any type of infection that cannot be controlled?

Well, as long as we burn organic fuels (and that's the only way to produce energy from them) we will have to produce carbon dioxide. We currently add about 8 billion tons of carbon dioxide to the atmosphere, every year, by burning different types of fuel. It doesn't seem like much if we remember that the total amount of carbon dioxide gas in the atmosphere is about 2280 billion tons, or almost 300 times the amount we add every year.

However, by the time we run out of fuel, in 2150 we will add a total of 60 thousand billion tons of carbon dioxide to the atmosphere, which means more than 25 times the total amount currently in the air. Some of this addition may be dissolved in the oceans, absorbed by the chemicals in the soil, or absorbed by fast-growing plants. But most of the amount will remain in the atmosphere.
If so, by the year 2150 AD, the percentage of carbon dioxide in the air will rise from the 0.04 percent that exists today, to something around 500 percent. (The oxygen content, which is XNUMX times that of carbon dioxide, will not be significantly affected by this change alone).

This high percentage of carbon dioxide will not be enough to suffocate us, but it will not be necessary. Carbon dioxide is responsible for what is called the greenhouse effect. It is opaque to the short waves of sunlight, but relatively opaque to the longer waves of infrared radiation. That is, the sun passes through the atmosphere, reaches the surface of the earth and warms it. At night, the earth radiates back the heat in the form of infrared radiation, and this radiation has problems trying to pass through the carbon dioxide. Therefore, the earth remains warmer than it would be if carbon dioxide were not present at all in the atmosphere.

If the amount of carbon dioxide present in the atmosphere today was only doubled, the average temperature of the earth would rise by 3.6 degrees Celsius. We could tolerate the hotter summers and the less cold winters, but what about the Greenland and Antarctic glaciers? At the higher temperatures, more ice will melt in the summer than will form again in the winter. The glaciers will begin to melt year after year at an ever-increasing rate and the sea level will rise mercilessly. When all the ice melts, the sea level will be at least 60 feet above today's level, and with every small tidal wave the ocean will wash the twentieth floor of the Empire State Building. All the valleys on the face of the earth, where the best agricultural lands are found, as well as all the concentrations of the population will be covered by the rising waters.

At the rate at which fuel consumption is increasing today, the glaciers will melt rapidly in about a hundred years. To prevent this, we could make an effort to switch to nuclear fission fuel, but in doing so we would create huge amounts of radioactive fallout, which would be an even more serious and dangerous problem than the carbon dioxide problem.

The safety barrier, thanks to pollution, and it doesn't matter what we do (apart from limiting the birth rate and energy consumption) is only a hundred years from now. If we don't develop massive nuclear fusion energy by the year 2070, the face of the country will change beyond recognition, irreparably harming humanity.
But do we have this hundred years at our disposal to manipulate it, if we don't limit the population?

Not only is the population growing, but it is becoming more and more unbalanced. The volumes, the urban accumulations, are the ones that increase the load of the human population in them, while the rural population actually decreases. This is mainly evident in the industrialized and 'advanced' areas of the world, but it is felt with increasing intensity everywhere, as the years pass.

It is estimated that the urban population on Earth doubles not every 35 years but every 11 years. By the year 2005, when the entire population of the unknown will have doubled, the population of the cities will increase ninefold or more.

This is a serious matter. We are already witnessing today the deterioration of the social structure; Corruption that is concentrated in excess in those advanced nations where urbanization is most prominent. In those nations the faults are mainly concentrated in the volumes, and especially in the most compressed parts of those volumes.

There is no disagreement that when living beings are crowded beyond a certain limit, various forms of pathological behavior are revealed. This has been verified in laboratory experiments with mice, and the newspapers as well as our personal experience should convince us that this is also true for human beings.
The population has been growing ever since the human race has existed, but never at the current rate, and never under such conditions of a full and overcrowded world. In previous generations, when man could no longer bear the crowd, he was able to escape to the sea, immigrate to America, or Australia, but now the earth is overflowing, and man can only reason in the crowd, it has become worse and worse.

And is social disintegration increasing only at the pace of population growth, or at the pace of urbanization? Will its level only double every 35 years, or even just every 11 years? For some reason I think not. I suspect that what determines the type of trouble we encounter around us - hostility, anger, outbursts, rebellions, withdrawal from society - is not only the number of people swarming around each person, but the number of possible interactions between the individual and the swarms of people around him.

For example, if person A and B are in close proximity to each other, they may fight. But the quarrel A against B is the only possibility. If A, B and C are in close proximity, then A may quarrel with B or with C or B may quarrel with C. While two people can have only one double-sided fight, three people can have three such fights, and four people can have six different fights. In short, the number of mutual encounters increases at a much faster rate than the number of people huddled per se. If the urban centers increase their population 9 times by the year 2000, then I fear that the level of social disorder and disintegration will increase (as a guess) fifty times, and I am quite sure that society will not be able to withstand this burden.

I conclude, therefore, that only the next generation is at our disposal to stop population growth, to reorganize our cities to prevent the pathological overcrowding that occurs today.

We have thirty years ahead of us - until the year 2000 - to do this, and this is an optimistic estimate. Unfortunately, I do not believe that the human race can fundamentally change its ways of thinking and acting in thirty years even under the most desirable conditions, and the conditions are far from desirable. It turns out that those who control human society are, for the most part, elderly people who live in comfortable conditions, who are frozen in the thinking frameworks of the previous generation, and who stick to the way of life they were used to.

It seems to me, therefore, that in the year 2000 or even earlier, the human social structure will completely collapse, and in the chaos that will follow as a result, approximately three billion people will die.

Also, there is not much chance of recovery after that, since in such chaos, it is easy to push the nuclear buttons quickly, and those who remain alive will face a world that will be poisoned by radiation for an immeasurable period of time. And as far as human civilization is concerned - this will be - the end.

 

What did Asimov expect in 1964 to be established in the Negev in 2014?