Asimov - An Exponentialist View
Bartlett - An Exponentialist View
Darwin - An Exponentialist View
Dawkins - An Exponentialist View
Drexler - An Exponentialist View
Ehrlich - An Exponentialist View
Malthus - An Exponentialist View
Sagan - The Secrets of the Universe
Savage - An Exponentialist View
Turchin - An Exponentialist View
Wallace - An Exponentialist View
Witting - An Exponentialist View

Human Global Ecophagy

External Links:

Wikipedia articles:

Isaac Asimov
Logan's Run
Make Room! Make Room!
Our Angry Earth
Spaceship Earth
Stand On Zanzibar
Zero Sum Game


 Isaac Asimov - An Exponentialist View

[In response to this question by Bill Moyers in 1988: What do you see happening to the idea of dignity to human species if this population growth continues at its present rate?] "It's going to destroy it all. I use what I call my bathroom metaphor. If two people live in an apartment, and there are two bathrooms, then both have what I call freedom of the bathroom, go to the bathroom any time you want, and stay as long as you want to for whatever you need. And this to my way is ideal. And everyone believes in the freedom of the bathroom. It should be right there in the Constitution. But if you have 20 people in the apartment and two bathrooms, no matter how much every person believes in freedom of the bathroom, there is no such thing. You have to set up, you have to set up times for each person, you have to bang at the door, aren't you through yet, and so on. And in the same way, democracy cannot survive overpopulation. Human dignity cannot survive it. Convenience and decency cannot survive it. As you put more and more people onto the world, the value of life not only declines, but it disappears. It doesn't matter if someone dies."  Isaac Asimov (Freedman, 2005, my bolding)

Science-Fiction and Non-Fiction

Isaac Asimov was a prolific author, best known for his science-fiction. Something Asimov says he deliberately avoided were the doomsday scenarios, including overpopulation, claiming that any science-fiction contributions made by him wouldn't have been missed due to the number of authors and the sheer volume of their doom and gloom novels. (Asimov, 1995, pp221-222). Some good examples are Harry Harrison's Make Room! Make Room! (filmed in 1973 as Soylent Green), William F. Nolan and George Clayton Johnson's Logan's Run (with a film of the same name made in 1976) and John Brunner's Stand On Zanzibar.

This didn't stop Asimov from expressing his "absolute horror at the growing overpopulation of the Earth" (Asimov, 1995, p.179). Typically Asimov did this in his non-fiction written work, and in interviews and lectures. Earth Our Crowded Spaceship (1974) and Our Angry Earth: A Ticking Ecological Bomb (1991) were probably Asimov's main work on overpopulation on our overcrowded planet. He is perhaps most often quoted on the subject of overpopulation due to his "bathroom metaphor" (see the Bill Moyers 1988 interview quotation above), and the claim that "...democracy cannot survive overpopulation." In the same interview he also stated that, although the world might reach 6.5 billion in 2000, the long-term sustainable population of the world is 5 billion (Freedman, 2005,p.136).

Reducing The Population Growth Rate

Asimov believed that contraception was the most humane solution to overpopulation and therefore preferable as a solution than abortion (Asimov, 1996). He believed that such contraception should be voluntary and could be achieved through female empowerment and emancipation (Freedman, 2005, pp.65-66):

"...I believe we have to liberate women if the race is to survive."

Asimov suggested that homosexuality should be encouraged as it reduces the birth rate (Asimov, 1996, p.278):

"I am not a homosexual myself but the population explosion is so dangerous that any device that cuts down the birth-rate without doing significant harm should be positively encouraged and defined as a right. Homosexuality is of these."

Asimov also saw a world government as a necessary part of the solution (Freedman, 2005, p.61).

The alternative to these measures, as Asimov saw it, was the unpleasant increase in the death rate. Asimov made specific predictions (Asimov, 1974[1], p.210) of famines in India and Indonesia starting in 1980, with potential global consequences for the human death rate for the year 2000. In a 1980 interview Asimov put the chances of civilisation still flourishing in 2010 at less than 50% (Freedman, 2005, p.61). These gloomy predictions didn't materialise, and for the moment science and technology found a way to feed our growing human population, thus undermining such prophecies of doom. Asimov, like Ehrlich, Bartlett and others before him and since, used a constant doubling period to illustrate his point. Note that it is clear this is just an illustration because Asimov lists variable population doubling periods over the last two thousand years (Asimov, 1974[1]).

If Asimov had illustrated his example of future growth with variable growth rates, and hence predicated variable future population doubling times to match the variability of the historical population doubling times, he would have at least predicated a range of  decades or centuries during which he anticipated localised famines and global population collapse. The strength of such an argument is that it is clear historically that populations grow at variable rates and thus experience variable population doubling times and not constant population doubling times. Thus, Asimov could have demonstrated quite unequivocally that variable rates of population growth are just as powerful and just as unsustainable as constant population growth rates and constant population doubling times. 

The Power of Progression

In The Stars In Their Courses Asimov the last two chapters includes related to what Asimov referred as the "utter catastrophe" of overpopulation, driven by the power of progression of exponential growth (Asimov, 1974[1], p.199). Despite living in comfort in the richest nation on Earth (then at its maximum power), Asimov felt a "helpless horror" at what he regarded as the unstoppable power of population (Asimov, 1974[1], p.199).

Asimov acknowledges counter-arguments that the standard of living has generally kept up with the growing population, as has what today we could call the human capital. He compares these arguments to the story of a man falling off the Empire State Building (Asimov, 1974[1], p.200):

"As he passed the tenth story, he was heard to mutter, 'Well, I've fallen ninety stories and I'm all right so far.'"

In examining the demographic history of our global population Asimov introduces the concept of the population doubling time which, he notes, by the middle of the twentieth century was 47 years (Asimov, 1974[1], p.203). Not pulling any punches, Asimov resorts to an ad hominem fallacy and refers to optimists who believe that science and technology can sustain such growth indefinitely as idiots. This includes those that still do not see the need for birth control.

With a starting population of 3.5 billion and doubling rate of 47 years Asimov calculates with mathematical certainty, through the power of "geometric progression", that we would reach 50 billion (or 46.6 C-pops - see below) in just 182 years  - that was A.D. 2151 for when Asimov was writing (Asimov, 1974[1], p.204). This is much like Asimov's own science-fictional world of Trantor, which had a population of 45 billion. Asimov imagined a similar world in Earth Our Crowded Spaceship where Earth has a population density equal to Manhattan (Asimov, 1974[2], p.60):

"There would have to skyscrapers everywhere. There would be hardly any open space. There would be no room for wilderness, or any plants or animals except those needed by human beings."

Asimov takes the population density of Manhattan (100,000 per square mile) and calculates that, given that the Earth's surface is 200,000,000 square miles, we would need 20 trillion people (or 18.19 D-Pops - see below) to reach the same population density globally, and that this would occur (still assuming a population doubling rate of 47 years) in just 585 years - that was A.D. 2554 for Asimov (Asimov, 1974[1]). Assuming this continued in space, our galaxy would hold 2.7 trillion trillion trillion in just 4,200 years, and the universe would hold 54,000 trillion trillion trillion trillion people (or 2.03 L-pops - see below) in just 6,700 years (Asimov, 1974[1]). By this stage the entire mass of the Universe has been converted into people, though Asimov notes that even the most extreme optimism couldn't survive the Earth turning into one enormous Manhattan (Asimov, 1974[1], pp.206-207).

For another Asimov example, and for an Exponentialist calculation of how long it would take humanity to eat the Earth, see Human Global Ecophagy.

Asimov's warns techno-optimists about the limited ability of science to maintain a food supply for a growing population (Asimov, 1974[1], p.207):

"Science, in other words, cannot keep up with populations no matter what it does."

With a population doubling rate of 47 years Asimov calculated humanity would replace the entire biomass on Earth in 624 years (in just over 13 population doublings). In other words, the Earth's total biomass would be composed entirely of humans in just 624 years time. Taking into account the fact that the fixed amount of solar radiation hitting the earth supports an estimated 200 million tons of biomass on Earth, Asimov argued that life on Earth is a zero sum game (Asimov, 1974[1], p.208):

"Every time the human population increases in mass by one ton, the mass of non-human animal life must decrease by one ton to make room."

This is reminiscent of what I call Darwin's wedge analogy.

Here I show Asimov's projected human consumption of the universe based on a population doubling period of 47 years with a starting population of 3.26 C-pops:

Pops (individuals) 1 2   4 8 16   32   64 128 256 512 1024
A-pops 1 2   4 8 16   32   64 128 256 512 1024
B-pops 1 2   4 8 16   32   64 128 256 512 1024
C-pops 1 2 3.26 4 8 16   32 46.6 64 128 256 512 1024
D-pops 1 2   4 8 16 18.19 32   64 128 256 512 1024
E-pops 1 2   4 8 16   32   64 128 256 512 1024
F-pops 1 2   4 8 16   32   64 128 256 512 1024
G-pops 1 2   4 8 16   32   64 128 256 512 1024
H-pops 1 2   4 8 16   32   64 128 256 512 1024
I-pops 1 2   4 8 16   32   64 128 256 512 1024
J-pops 1 2   4 8 16   32   64 128 256 512 1024
K-pops 1 2   4 8 16   32   64 128 256 512 1024
L-pops 1 2 2.03 4 8 16   32   64 128 256 512 1024
M-pops 1 2   4 8 16   32   64 128 256 512 1024
N-pops 1 2   4 8 16   32   64 128 256 512 1024
O-pops 1 2   4 8 16   32   64 128 256 512 1024
P-pops 1 2   4 8 16   32   64 128 256 512 1024
Q-pops 1 2   4 8 16 36.08 32   64 128 256 512 1024

Table A. Using my New Malthusian Scale, the projected human population doubling every 47 years (so each row represents 470 years).

Note:  1A-pop = 1024 pops, 1B-pop = 1024 A-pops, 1 C-pop = 1024 B-pops etc.
3.5 billion people = 3.26 C-Pops, 50 billion = 46.6 C-pops, 20 trillion people = 18.19 D-Pops, 2.7 trillion trillion trillion = 2.03 L-pops and 54,000 trillion trillion trillion trillion = 36.08 Q-pops.

An easy way to calculate which row of the New Malthusian Scale each of Asimov's target populations should be on is to divide the number of years to reach the target by 470 (the number of years per row). For example, from the starting population of 3.26 C-Pops that's 20 trillion people in 585 years (just over one row of 470 years), 2.7 trillion trillion trillion people in 4,200 years which is almost 9 rows (4200 / 470 = 8.9), 54,000 trillion trillion trillion trillion in more than 14 rows (6,700 / 470 = 14.25).

To convert decimal into the New Malthusian Scale simply keep dividing the decimal total by 1024 until you get a number between 1 and 1024 inclusive.

There are some problems with Asimov's examples of population doubling. Firstly, he rather awkwardly uses decimal notation to describe a binary idea - population doubling. Secondly, in his book Asimov writes out the full number of zeros for each of the larger numbers. I can just imagine readers' eyes glazing over. Using the New Malthusian Scale is easier as it's much like the way we sometimes describe binary-natured kilobytes, megabytes, gigabytes etc. Thirdly, Asimov uses a constant population doubling period which  - although illustrative - is not realistic. Populations do not grow via constant growth rates, and do not double at a constant rate either. This is the problem with a similar explanatory approach taken by Malthus, Ehrlich and Bartlett for example. Refer to the following articles to read the Exponentialist criticism of such an approach:

Reverend Thomas Malthus - An Exponentialist View
Paul R. Erhlich and the Prophets of Doom - An Exponentialist View
Albert Bartlett - An Exponentialist View

Of course, it would be simpler if examples of population doubling simply used the New Malthusian Scale with whole number starting populations.

A Finite World

Asimov stated that (Asimov, 1974[1], p.214):

"It is no longer possible to solve the real problems of our planet by working on the assumption that the world is infinite."

It was Malthus who most famously introduced the concept of the limits to growth imposed by Earth itself (Malthus, 1798):

"But to make the argument more general and less interrupted by the partial views of emigration, let us take the whole earth, instead of one spot, and suppose that the restraints to population were universally removed. If the subsistence for man that the earth affords was to be increased every twenty-five years by a quantity equal to what the whole world at present produces, this would allow the power of production in the earth to be absolutely unlimited, and its ratio of increase much grater than we can conceive that any possible exertions of mankind could make it. Taking the population of the world at any number, a thousand millions for instance, the human species would increase in the ratio of - 1,  2,  4,  8,  16, 32, 64, 128, 256, 512, etc. and subsistence as 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 etc. In two centuries and a quarter, the population would be to the means of subsistence as 512 to 10: in three centuries as 4096 to 13, and in two thousand years the difference would be almost incalculable, though the produce in that time would have increased to an immense extent"

Yet for over 200 years people and governments have continued to deny the truth that the world's resources are finite.

Asimov argues that our only real hope of survival as a species is the colonisation of space, that even a human colony on a finite Moon would be "infinitely worthwhile" (Asimov, 1974 [1], p.221). How would this help, you might wonder? For a start, Asimov desperately hopes it will be a multi-national effort, reducing national concerns to insignificance and elevating human survival into the space (Asimov, 1974 [1], p.221). He doesn't rate our chances highly, but, as he says (Asimov, 1974[1], p.222):

"...I must hope."


Asimov, Isaac, The Stars In Their Courses. Panther. 1974[1]

Asimov, Isaac, Earth Our Crowded Spaceship. Abelard-Schuman. 1974[2] - written for young adults

Asimov, Isaac, I Asimov: A Memoir. Bantam. 1995.

Asimov, Isaac, Yours, Isaac Asimov - A Life In Letters. Main Street Books. 1996.

Freedman, Carl (editor), Conversations with Isaac Asimov. University Press of Mississippi. 2005.

Malthus, Thomas Robert, An Essay on the Principle of Population. J. Johnson. 1798. (1st edition) Library of Economics and Liberty.  

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Copyright 2009 David A. Coutts
Last modified: 05 January, 2011