This is a follow up to my post Robert Zubrin; The Merchants of Despair - Initial Reaction
In Merchants of Despair Zubrin mocks
the concept of limits to growth or finitude as he terms it. He calls it a “quasi-religious concept upon which the
Malthusians stake the ultimate truth of their dogma” (Zubrin, 2012, p.123).
You’d expect then that
Zubrin would take some care in demolishing this foundational dogma of his hated
enemies, the Malthusians. Let’s see how he does.
Zubrin asks (Zubrin,
“In what sense can a resource be regarded as finite if you not only
never run out, but never experience any shortage? Our ability to turn the
matter of planet into useful items is increasing daily. Someday it may all be
useful.” (my bolding)
Zubrin must truly
believe then that the Earth is an infinite resource that humanity can draw upon
forever. But then, Zubrin acknowledges that the Earth has a finite mass of 6
trillion trillion (6 x 1024) kilograms. So the finitude of the Earth is not a quasi-religious concept but a simple scientific fact. This seems a very shaky
start for Zubrin, acknowledging that the Earth is indeed finite.
Zubrin explains that
if the human population increased a thousandfold from 6 billion (this was our
population in 1999) to 6 trillion we’d still have a trillion kilograms of mass
available to each one of us.
Mathematically this is
true, as far as it goes. However, there are a number of considerations Zubrin
does not discuss:
- How quickly might this occur?
- What sorts of technologies might allow us to
support such a vast human population?
- What would the ecological impact be to the rest
of life on Earth if we increase our human population to 6 trillion?
- What would the human impact be like of living
on a world with a thousand times the number of people alive?
- Will some nations expand their populations at
the expense of others, in a repeat of Hitler’s quest for lebensraum (living space)?
- is the future that we all want?
A useful rule of thumb
for calculating population increase is The Rule of 70. Put simply, if you take the annual
growth rate and divide it into 70 then you get the population doubling period.
Taking examples from recent human population growth, if the annual growth rate
is 1% then the doubling period is 70 years and if the annual growth rate is 2%
then the doubling period is 35 years.
Hence, it took just 39 years for our global population to double from 3
billion in 1960 to 6 billion in 1999.
So how do we estimate
how long it would take for our 6 billion to increase by a ratio of one
thousand? Well, 10 population doublings slightly exceeds a thousandfold
increase (210 = 1024). Hence, at a 2% annual growth rate 10 population
doublings would take just 350 years (35 x 10) and at a 1% annual growth rate it
would take 700 years (70 x 10).
Note that if the annual growth rate were to vary between 1% and 2% then
our global human population would still increase more than a thousandfold somewhere
between 350 and 700 years from now.
So in just 350 to 700
years, at very modest annual growth rates, our human population would be 6,144
billion (6 x 1024) or just over 6 trillion. Can we do it? Should we do it?
Zubrin’s vision will
require some pretty advanced technologies in order to manipulate Earth’s matter
to meet an ever-growing human population. One of the most futuristic
technologies is perhaps K Eric Drexler’s vision (Engines of Creation, 1990) of molecular
nanotechnology, precision engineering of non-organic material at the molecular
level. See K. Eric Drexler - An Exponentialist View for
more. However, in his earlier work
Space Creating a Space Faring Civilzation
Zubrin (p 240) suggests that the absence non-organic self-replicating entities
and the omnipresence of organic self-replicating entities combine as strong
evidence against the possibility of “Drexler-style nanotechnology.” Zubrin is
betting on bioengineering and “human-improved microorganisms” instead. Time will tell, but it’s interesting
that Zubrin’s blind faith in human ingenuity does not extend to Drexler’s
And it’s a pity then
that Zubrin hasn’t learn to respect the lessons that Malthus taught us back in
1798 (An Essay on The Principle of Population) as Drexler has (Drexler, 1990):
population and resources will remain important because the exponential
growth of replicators (such as people) can eventually overrun any finite
When it comes to
imagining a world of filled with humans we cannot do better than the great
American science-fiction author Isaac Asimov (refer
Isaac Asimov - An Exponentialist View for more). In one of his non-fiction works (Stars In Their Courses) Asimov imagined
a world of 20 trillion (just two more population doublings from Zubrin’s 6
trillion would exceed this, at 24 trillion) with a population density
everywhere equivalent to New York’s Manhattan Island (Asimov, 1974):
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."
Like Drexler, Asimov warns us that
in the end (Asimov, 1974):
in other words, cannot keep up with populations no matter what it does."
However, Asimov’s most famous quote on the impact of
overpopulation comes from an interview with Bill Moyers in 1988:
“… 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
This is the Hellish
future that Zubrin promotes for humanity in the coming centuries here on
Earth. His stark lack of care for non-human life is obscene, and his locust
mentality for Earth’s resources to be turned into an endless sea of human flesh
is just appalling.
Of course, the obvious
next question is what next? What happens after we get to 6 trillion? After all, Zubrin is meant to be
dismantling the foundation dogma of the Malthusians that the Earth is finite.
So why does Zubrin stop at 6 trillion? Well, it’s a big number of people and
there’s still plenty of matter to go around (a trillion kilograms
each…hooray!). By avoiding a timeframe, or explaining what sort of world it
would be like, Zubrin promotes the positive and omits the negative.
In fact, Zubrin then
avoids the challenge he set himself (to destroy the dogma that Earth is finite)
by making the leap into space (Zubrin, 2012):
“Long before we have six trillion people, or sixty billion for that
matter, we will have mastered space travel.”
So Zubrin has cheated
and sidestepped the question of what happens next on a finite Earth. Why? Because he knows that the
Malthusians are right!
Ah, you cry, but Zubrin is right as once we’re in space
human expansion is potentially limitless!
Well, if the Earth is in fact finite then so too is our
Solar System. Each asteroid, each comet, each planet, each moon and every other
solar system will also represent localized limits to growth that space-faring
replicators such as humans will be forced to face.
I think it's also worth repeating the idiotic claim of one of Zubrin's heroes, Julian Simon, who won his famous (but comparatively irrelevant) bet on commodity prices against one of Zubrin's hated Malthusians, Paul R Ehrlich (Simon, 1995):
"We now have in our hands - in our libraries really - the technology to feed, clothe and supply energy to an ever-growing population for the next 7 billion years."
Simon apparently revised that claim down to 7 million years when challenged. Professor Albert Bartlett's answer at the time was (Harding, 1999):
"Let us, Professor Bartlett said, assume that 7 million is what Simon had in mind. Assuming the present world population of six billion and the recent rate of population growth of 1 percent per year, how long would it take for the human population to equal all the atoms of the universe. The answer is shocking: just 17,000 years."
Also, do not forget that we left six trillion humans on
Earth some time after we mastered space travel. So, Mr. Zubrin, what happens to
that human population on Earth? If
they keep growing as you say they can - thanks to their limitless ingenuity - then they will consume the entire Earth
and all non-human life on it. Read my article Human Global Ecophagy to see just
how quickly humans could consume the entire planet and turn it all to human
flesh…roughly speaking it could take as little as 1,600 to 3,200 years.
In conclusion then it is obvious that the mocking Mr. Zubrin
has failed to make his point. The Earth is, after all, finite. The Malthusians
are right on this point.
However a finite world does not automatically mean, as Zubrin (2012) claims (p252), that:
“If the idea is
accepted that the world’s resources are fixed with only so much to go round,
then each new life is unwelcome, each unregulated act or thought is a menace,
every person is fundamentally the enemy of every other person, and each race or
nation is the enemy of every other race or nation….Only in a world of unlimited
resources can all men be brothers.”
What about the
possibility that we promote education (especially for women), health and
longevity in the Third World in order to foster a demographic transition and
reductions in population growth rates? Every child would be even more precious
if we voluntarily restricted the size
of our families.
What about the possibility
that in the future wealth and consumption are more equitably distributed rather
than focussed in the Western democracies?
What about the
possibility that many humans respect and care for non-human forms of life on
Earth and for biodiversity? What about the possibility that humans are willing to protect other life
on Earth at our own expense?
Above all, we must
avoid Zubrin’s blind faith in limitless human ingenuity (Zubrin, 2012, p.252):
“That is why we must reject antihumanism and embrace instead an ethic
based on faith in the human capacity for creativity and inventiveness.”
Zubrin’s unscientific, irreponsible and dishonest blind faith
will push us towards human global ecophagy and the worst of all holocausts not
just for humanity but also for all life on Earth.
Wake up…we live in a
finite world (6 x 1024 kilograms, according to Zubrin himself) and
we therefore need to plan to live sustainably on Earth even as we reach for the
Zubrin presents a false dichotomy, arguing our choice is either sustainability or growth. But we can do both - live sustainably where we must (such as Earth), and expand into space when we can.
Asimov, Isaac. The Stars In Their Courses. Panther. 1974
Drexler, K. Eric. Engines Of Creation - The Coming Era of Nanotechnology. Oxford University Press. 1990.
Hardin, Garrett, The Ostrich Factor: Our Population Myopia. 1999
Simon, Julian, The State of Humanity: Steadily Improving, Cato Policy Report, 1995 (based on the introduction to his 1995 book, The State Of Humanity)
Zubrin, Robert. Merchants of Despair Radical Environmentalists, Criminal Pseudo-Scientists, and the Fatal Cult of Antihumanism. New Atalantis. 2012.