4.
Malthus as a Prophet of Non-Progress.
Suffering
and crisis are
ineliminible components of the human condition. Resource
limitations guarantee that all societies will experience periodic
difficulties. If this were not the case, there would be no reason for
people to have to adapt, struggle, feel, or think.
As
I see it, Malthus discovered a deep philosophical principle.
Evil is necessary to life, because it is only through the struggle to
overcome it that we become fully human. It is absurd to suppose that
the right political or economic system will one day eliminate all
evil and struggle from every society in the world. This is not
supposed to discourage us from doing good and charitable deeds, but
encourage us to pursue them on a local scale. Between us and Malthus
lie the twin catastrophes of Fascism and Communism. If Malthus’s
Principle was prophetic of anything, it was that world-progressive,
utopian ideologies like these are fundamentally irrational.
5.
Birth Control: Solution or Mirage?
Granted
that all of nature and most societies have been subject to the
Principle of Population, might it still not be possible to rationally
convince the world to use birth control and finally rid ourselves of
this obstacle to progress? Aren’t organizations like Planned
Parenthood already trying to do this?
As urbanization continues across the globe, average
fertility rates are falling. According to the UN (2010), between 1950
and 1955 the total fertility rate (births per woman) was about 4.95.
Between 2010 and 2015, it was 2.36. So it is declining and it doesn’t
seem unreasonable, on the face of it, that this trend will continue
and eventually free the world from the “Malthusian Trap.”
However, I’m going to argue in the following sections
that this is an irrational hope.
Malthus
originally argued that the “passion between the sexes” could
never be overcome. It is ubiquitous in nature. Every plant and animal
species produces, on average, more offspring than can reproduce
themselves. This is no surprise on Darwin’s theory of natural
selection. Populations that do not reproduce at their maximum rate
will always give way to those that do. As we’ll discuss shortly,
creative evolution requires mutation as well as natural selection.
Without natural selection, mutation leads to uncontrolled variation.
Without mutation, a species has no adaptability.
Could it be that the tendency of humans and animals to
reproduce exponentially is a hardwired result of evolution? A
tendency that is needed for a species to continue to spread,
diversify, and adapt? In the following sections I’ll argue that
this is indeed the case. I’ll attempt to demonstrate that Darwin’s
theory can be stated as a law of nature that mandates a balance
between creativity and destruction. On this view, neither progress
nor regress is possible in the long run, whether we are talking about
plants, animals, or human civilization.
5. Darwin’s Question.
Along with social upheavals, the 18th century
Enlightenment created tremendous scientific upheavals as well. As
Europe became wealthy on transoceanic trade, specimens of plants,
animals, and minerals were brought back from around the world,
overthrowing previous theories in geology and biology. Scientists
began to speculate that the world was at least millions of years old,
that species might have changed over these vast periods of time, and
that different species might have even descended from a common
ancestor.
From this observation and several others, Darwin began to speculate on evolution. Taxonomy and comparative anatomy also provided good evidence that most or all species had evolved from a common ancestor. “What can be more curious,” he wrote, “than that the hand of a man, formed for grasping, that of a mole for digging, the leg of a horse, the paddle of a porpoise, and the wing of a bat, should all be constructed on the same pattern, and should include the same bones, in the same relative positions?” The big question was how it had happened. What process had allowed species to change and adapt so meticulously over time? Geologists had been able to explain dramatic geological change through the action of wind, waves, and dust over millions of years. But biology was missing a theory of how complex adaptations arose. Use and disuse didn’t seem to explain anything. Why would using an organ make it grow larger rather than smaller? How had a device as complex and intricate as the eye arose by the chance influence of the environment?
6.
The Influence of Malthus on Darwin.
Prior
to his reading of Malthus, Darwin “perceived that selection was the
keystone of man's success in making useful races of animals and
plants. But how selection could be applied to organisms living in a
state of nature remained for some time a mystery” (Autobiography,
1887).
Animal breeding by humans had succeeded in creating animals as
different as Dachshunds and Great Danes from a single common
ancestor. Could there be a similar process by which nature built up
new varieties? But how could the random processes of blind nature
compare with careful selection by animal breeders?
In
his Autobiography,
Darwin explains his breakthrough reading Malthus:
In
October 1838, that is, fifteen months after I had begun my systematic
enquiry, I happened to read for amusement Malthus on Population,
and being well prepared to appreciate the struggle for existence
which everywhere goes on from long-continued observation of the
habits of animals and plants, it at once struck me that under these
circumstances favourable variations would tend to be preserved, and
unfavourable ones to be destroyed. The result of this would be the
formation of new species. Here then I had at last got a theory by
which to work; but I was so anxious to avoid prejudice, that I
determined not for some time to write even the briefest sketch of it.
(Darwin, 1887)
He
called this process by which favorable variations were preserved
natural
selection,
by analogy with the process of artificial selection that humans use
to make new breeds of animals and plants.
Because all animal and plant
populations grow exponentially, they are subject to constant
pressures from lack of resources. These pressures cause the less
well-adapted to die or have fewer offspring than others. If a certain
plant produces a hundred seeds, on average only one can grow to
maturity to produce its own seeds, and this one will tend to be
better-adapted. In this way the better-adapted survive and pass on
their traits.
But Darwin knew that natural
selection alone could not account for evolution. Selection was a
purely destructive force. It did not create new varieties but only
destroyed the ones that were less well-adapted. In order for natural
selection to produce to species, it needed a constant supply of new
variations to work on. And these variations had to be heritable, or
they could not lead to permanent change in the species.
Today
we know that heritable traits are coded in DNA. Mutations in DNA
create new variations, providing raw material for natural selection.
In Darwin’s day, the mechanisms of inheritance were obscure. He
devoted several chapters of the Origin
of Species to
arguing, using evidence from animal breeding and natural history,
that heritable variation was common throughout the plant and animal
kingdoms, even if its details were still unknown.
7.
Darwin’s Theory in a Nutshell.
Biologists
have since refined Darwin’s theory to a set of three conditions,
known as Lewontin’s Criteria. They are based on a mathematical
formalization of Darwin's theory by Mary Williams published in 1970.
In the same year the biologist Richard Lewontin published a paper,
“The Units of Selection,” in which he points out that natural
selection is guaranteed to occur in any population which satisfies
the following three criteria:
1. Different individuals in a
population have different mental and physical traits (“Variation”).
2. This variation is heritable
(“Heritability”).
3. Different variants have
different rates of survival and reproduction (“Differential
Fitness”).
It is widely recognized among
biologists that all systems which satisfy these conditions undergo
natural selection.
Variation is also referred
to as diversity. If all the individuals in a population have the
same traits, there can be no evolution. Natural selection only works
on differences.
Heritability just means
that traits are passed from one generation to the next. If the traits
aren’t passed down, then new variations will be lost.
Differential fitness refers
to the fact that some traits will spread more quickly than others.
Fitness is a biological term meaning average number of
offspring per parent. Among humans, if the average couple has 2
children, that will be fitness 1. If the average couple has 4
children, that’s fitness 2. An average of 1 child means fitness of
0.5. Traits with a fitness above 1 will quickly spread and come to
predominate.
If you add mutation to the picture
to provide new variations, you get evolution. In fact one can combine
these conditions with the mutation requirement and state evolution as
a single condition:
Evolution is when heritable
variations (mutations) arise that make a difference to how many
offspring are produced.
This is Darwin’s entire theory
of evolution in a nutshell.
Say you’ve got a mutation that
causes a certain organism to produce slightly more offspring. If this
mutation is passed down, then it’s offspring will also have more
offspring. The spread of this variant will thus be exponential. Since
there are limited resources, by Malthus’s Principle, other variants
will decrease in the population until they disappear.
Ultimately, Darwin’s theory
explains the mystery of why every organism tends to reproduce at an
exponential rate.
8. A Note on the Terminology of
“Selection.”
Differential
fitness is commonly referred to as “selection” by biologists, and
I will use the same term here. Originally, Darwin drew a sharp
distinction between natural
and artificial
selection, because his challenge was to argue that species could
evolve without the intervention of a higher being. It was well known
that animal breeding—“artificial selection”—could produce
from the same species animals as different as St. Bernards and
Terriers. Darwin had to show that this process was possible in the
wild, and he called this “natural selection.”
In this book we are discussing
selection among humans. When the distinction between natural and
artificial selection is unnecessary, I will simply use the term
“selection,” which refers to either kind. “Natural selection,”
as with animals, will refer to selection due to untimely death,
individual mate choice, or difficulty reproducing. However, to
maintain continuity with past literature on human evolution,
artificial selection of humans will be referred to as “eugenics.”
This term will be used for any scenario where the natural processes
of survival, mate choice, or reproduction are interfered with by
custom, law, or decree.
Animals in the wild have no
choice. They act according to instinct and suffer without
contemplating the big picture. Many suppose that birth control helps
separate us from animals, that it makes us special. In fact many
scientific authors like to say that we’ve overcome Darwinian
evolution. “If each family had only two children,” writes
biologist Cavalli-Sforza triumphantly, “there would be no natural
selection.” Richard Dawkins writes in The Selfish Gene (1978):
“We are built as gene machines and cultured as meme machines, but
we have the power to turn against our creators. We, alone on Earth
can rebel against the tyranny of the selfish replicators.” Steve
Jones, in The Language of Genes (1995) writes: “It may even
be that economic advance and medical progress mean that humans are
almost at the end of their evolutionary road, that we are as near to
our biological Utopia as we are ever likely to get.”
The reality is that most of
humankind is still subject to natural selection. Most societies,
religions, and individuals have fertility rates above two. In fact
most preindustrial cultures explicitly discourage birth control. (For
a variety of detailed examples see Carol P. MacCormack and Marilyn
Strathem, eds., Nature, Culture, and Gender, 1982.) During the
period 2000-2005,there were 33 nations (totaling 720 million
inhabitants) with average birthrates of at least 5 children per
female, 17 nations (totaling 240 million people) with average
birthrates of at least 6, and 3 nations (totaling 45 million people)
with birthrates of at least 7. These birthrates are comparable to
those in the preindustrial West, which were generally in the 5-8
range. These nations are growing significantly faster than the rest
of the world, with annual growth rates between 2 and 4.5%, compared
to the world average of 1.17%. Even within the United States, there
are religious groups, such as the Mennonites, who oppose birth
control on principled grounds and thus have a consistently higher
fertility than the rest of the country.
At the same time, many industrial
countries have birth rates below replacement levels, so that their
populations are in fact declining at exponential rates. Countries
with fertility rates below 1.5 children per female include China,
Japan, South Korea, Lithuania, Ukraine, Spain, Italy, Hungary, and
Austria. In fact, the European Union as a whole has an average
fertility rate of about 1.50. Assuming that children tend to adopt
the birth control practices of their parents, it appears that natural
selection will eventually lead to the predominance of those cultures
that resist the use of birth control.
Many express the hope that by
industrializing and educating other nations we may eventually reduce
all fertility rates below two. What people usually do not
stress is that every society in the entire world would have to
consent to this for it to work in the long run. If only one society
of, say, a million people retained a birth rate of three children per
family, this society could number in the billions within four
centuries. If the Amish maintain their current rate of population
growth, German-speakers will outnumber English-speakers in North
America within two hundred years.
This is natural selection at work.
A similar explanation may account for the disappearance of Pagans and
Gnostics who used abortion and infanticide as means of family
planning in late Antiquity, and the spread of early Christians who
discouraged these practices.
I am not sure how to prove
that birth rates cannot be lowered to replacement levels in every
society worldwide. It is conceivable that a world government might be
put in place that sterilizes all women after two children, for
example. Personally I find such schemes abhorrent. Rest assured if
that happened you could count me among the freedom fighters. But to
gain a better understanding of the principles of evolution, let’s
assume for the sake of argument that birth rates have been reduced to
two everywhere and indefinitely.
To begin with, notice that in this
scenario there would be no natural selection. Everyone would
reproduce at the same rate, so there would be no differences in
fitness. New mutations would arise, but they would give no one any
advantage or disadvantage. Instead, every generation would accumulate
more random mutations and pass them on.
How do we know there would be
mutations? We know because inheritance is not perfect. When DNA is
copied, there are sometimes mistakes. It is estimated that about 400
mutations occur between each generation of human. Most of these
mutations don’t make any difference. A few are harmful, and a very
rare few are beneficial. It is much more common for mutations to have
detrimental effects than beneficial effects. Mutations are more often
harmful than helpful for the same reason that cars tend to run worse,
and not better, as the get older. Random changes to any structure
will tend toward disorder, as we know from the theory of
thermodynamics in physics.
In most cases these harmful
mutations are eliminated by natural selection. As I’ve mentioned
most plants and animals produce many more offspring than can survive
or reproduce. Typically only 1-30% of offspring succeed in reaching
adulthood and reproducing themselves. In this way mutation and
natural selection keep each other in check. Mutation provides new
variety, natural selection eliminates unfit varieties.
Birth control, in other words,
would appear to disrupt the balance between mutation and natural
selection. That this might be so has been feared for over a century.
A shallow understanding of these principles of evolution, however,
led to the infamous eugenics movement. It is worth pausing to
consider the history of eugenics before proceeding, because nothing
has done more to muddy the waters of the debate over whether and how
Darwin’s theory can be applied to humans.
10. Eugenics as Tyranny.
Eugenics is a social movement
responsible for the sterilization of millions in the early-to-mid
twentieth century, and used by the Nazis to justify the murder of
millions. There are still eugenic societies around the world, though
most have been forced to keep a low profile in the wake of the
atrocities of World War II.
Let me clarify my personal views
before we go any further. I am not a eugenicist in any sense of the
word. Eugenics is based on the idea that humankind as a whole can be
improved or degraded. I don’t believe either is possible. Freedom,
family, and universal love are held as sacred values by all
religions. In order for these to be possible, each individual must be
valued as the incomprehensibly complex, creative, and spiritual being
that he or she is. Any and all state-run programs that interfere in
human reproduction—one of the highest expressions of human love and
creativity, the bringing into the universe of a new incomprehensible
being—are intrinsically evil and should be opposed. This includes
any program that impedes a human’s right to reproduce, whether for
the purpose of limiting the world population, or for the purpose of
“improving” its genetic stock. Both of these goals have been
integral tenants of the eugenics movement.
The origin of the most infamous
eugenic societies lay in the late 19th century, before the
mechanisms of heredity were very well understood. Francis Galton, a
statistician and sociologist, worried that the poor were outbreeding
the “gifted” in his influential book Hereditary Genes
(1887). Karl Pearson, another statistician, agreed that we needed to
“check the fertility of the inferior stocks” (The Grammar of
Science 1892).
Reactions varied. Many put up
stalwart resistance. In his 1893 essay “Evolution and Ethics,”
T.H. Huxley, an ardent supporter of Darwin’s theory, condemned the
idea of eugenics because it failed to take into account both its
impracticality and the immoral effects it would have on society.
Arguing for its impracticality he wrote:
I doubt whether even the keenest
judge of character, if he had before him a hundred boys and girls
under fourteen, could pick out, with the least chance of success,
those who should be kept, as certain to be serviceable members of the
polity, and those who should be chloroformed, as equally sure to be
stupid, idle, or vicious. The “points” of a good or of a bad
citizen are really far harder to discern than those of a puppy or
short-horn calf; many do not show themselves before the practical
difficulties of life stimulate manhood to full exertion.
And against its morality he argued
that it would require “preternatural ruthlessness” and “drastic
thoroughness” and that “human society is kept together by bonds
of such singular character, that the attempts to perfect society
after his fashion would run serious risk of loosening them.”
But the movement only grew in
strength. In 1922 the social critic G.K. Chesterton was moved to
publish a lengthy and brilliant—if somewhat unscientific—refutation
of eugenics entitled “Eugenics and other Evils.” He argued that
love is personal and should not be regulated by the state. He called
any such regulation “tyrannical” and rhetorically asked to
whom “such risks of tyranny could be trusted.” He pointed
out, quite rightly, that the “complexity [of heredity] must be
nearly unfathomable ...”
But the heavy mathematical
artillery, as it unfortunately happened, fell into the lap of
eugenics. Mathematicians J.B.S. Haldane and R.A. Fisher—who were
skeptical of eugenics—were the first to develop a mathematics
describing natural selection among discrete (Mendelian) genes. This
meant that processes of natural selection and mutation could finally
be combined into one model, an important step in filling in the gaps
in Darwin’s theory of inheritance. But the most influential
mathematical biologist was the eugenicist Julian Huxley, who wove
together Fisher and Haldane’s theories, field biology, social
anthropology, statistics, and genetics into his masterwork,
Evolution: the Modern Synthesis in 1942. Huxley was vice
president of British Eugenics Society from 1937-1944 and President
from 1959-1962. He helped encourage many of the mass sterilizations
that happened throughout Europe and North America during this time.
After World War II eugenics became
associated with Nazism, so Huxley coined the term “Transhumanism”
for it in his 1957 essay, and the society changed its name to the
Galton Institute in 1989.
In 1964, Huxley published
Evolutionary Humanism, which argued:
To effect [future improvements of
our species we] must first of all check the processes making for
genetic deterioration. This means reducing man-made radiation to a
minimum, discouraging genetically defective or inferior types from
breeding, reducing human overmultiplication in general and the high
differential fertility of various regions, nations, and classes in
particular. Then [we] can proceed to the much more important task of
positive improvement. (p. 252)
Nevertheless, eugenics continued
to decline in the wake of the horrors of Nazism, though few attempts
at scientific, quantitative refutation were attempted. Stephen Jay
Gould's Mismeasure of Man (1981) did challenge the use of IQ
testing that the eugenic program depended on. Gould argued that
people were attempting to reify a concept that had no objective
basis, and that rank-ordering complex things like intelligence was
inherently nonsensical. Political tracts such as Not in Our Genes
(1984) by R.C. Lewontin, Steven Rose, and Leon J. Kamin offered
woefully indecisive objections that nevertheless few dared to
publicly question:
We reject [the nature-nurture]
dichotomy. We do assert that we cannot think of any significant human
social behavior that is built into our genes in such a way that it
cannot be modified and shaped by social conditioning ... . Yet, at
the same time, we deny that human beings are born tabulae rasae
..." (267)
Despite the lack of any truly
rigorous analysis, the view that heredity is irrelevant to
discussions of the human population has become the public consensus
among scientists. This has become very clear in the wake of the
indignant reactions to Herrstein and Murray’s 1994 book The Bell
Curve, which presented evidence that IQ was heritable,
differed among races, and had a measurable effect on future income.
The debate over IQ measurements
and race is ultimately what logicians call a red herring, a
distraction from what was originally at stake. What of the
eugenicists’ original concern, namely, that modern Western society
lacks natural selection to check mutation? The fear of raising
further outcries has discouraged critical discussion. As far as I can
tell no reasoned consensus about human evolution has been reached.
11. Can Mutation be
“Overcome”?
Let’s
return to Julian Huxley’s original point, which was the question of
whether humanity can reach utopia when our DNA is constantly mutating
in ways that are usually harmful. Huxley believed that we must
control our population to avoid running out of food. At the same time
he saw that birth control would weaken the force of natural
selection, which was why he wanted a program of eugenics to eliminate
harmful mutations from the human gene pool.
A
few subsequent authors seconded this proposal. In his 1978,
Pulitzer-prize winning On
Human Nature,
biologist E.O. Wilson brought up the apparent problem of human
mutation and said that eventually we will have the knowledge to put
in place “democratically contrived eugenics” to counteract it.
Harvard
biologist Stephen Jay Gould made a heroic—if unsuccessful—attempt
to challenge this assumption in his posthumous tome The
Structure of Evolutionary Theory:
This situation supposedly raises
a forest of ethical questions about double-edged swords in the cure
of diseases arising from genetic predisposition, the spread of genes
for poor vision in a world of cheap eyeglasses, et cetera ad
infinitum. (Pardon my cynicism based on some knowledge of the
history of such arguments, but the neo-eugenical implications of
these claims, however unintended in modern versions, cannot be
ignored or regarded as just benignly foolish.)
...
This
entire line of fallacious reasoning, with all its burgeoning
implications, immediately collapses under a speciational
reformulation. Once people understand Homo sapiens as a biological
species, not a transitory point of achievement, the apparent paradox
disappears [...] Most species-especially those with large,
successful, highly mobile, globally spread, environmentally diverse,
and effective panmictic populations-remain stable throughout their
history [...]. Change occurs by punctuational speciation of isolated
subgroups, not by geologically slow anagenetic transformation of an
entirety.
Gould is referring to a theory in
evolutionary biology that large populations do not show very much
evolutionary change. This theory is controversial and opposed by a
number population biologists, since it neglects the greater flux of
new mutations that a large a population can select from. Be that as
it may, Gould’s objection does not actually apply to the case of
humans using birth control. There are no examples of any species
aside from humans that are not continually subject to natural
selection. For a species to remain “stable” as Gould puts it,
natural selection must act continually to counter mutation, as all
textbooks in population biology teach. (For a simple mathematical
argument, see Appendix 2).
So if Julian Huxley and E.O.
Wilson’s arguments remain untouched, are they and the other quieter
eugenicists right then? Are we bound to control human mutation lest
it spiral out of control?
Let’s remember once more that we
are talking about a hypothetical scenario where all birth rates in
the world have been reduced to two. This does not seem doable except
by world tyranny, but we are assuming it is possible for the sake of
argument.
To control human mutations by
engineering, we would have to genetically engineer every new baby on
the planet. Even if we could afford this, how can we be sure our
method for reducing mutations is infallible? It’s been shown that
multiple genes code for multiple things. What about sexual
recombination giving us new genetic linkages and traits? Maybe one
way to stop all mutation would be to simply clone each generation
from a DNA database. But what isn’t horribly wrong with such
a scenario? Every generation would be biologically the same. No new
genetic combinations could be made, for fear of mutation. Not only is
this plan implausible, but also monstrous.
If anyone sets up a world
government this controlling, let’s overthrow it.
But
where does this leave us? Is humanity hopeless? Quite the contrary.
We are back to Malthus’s original conclusion. You cannot completely
eliminate suffering and evil from life. Mutation carries with it both
good and bad. It is the source of new talent, new genius, and new
diversity among humans. To rid ourselves of mutation would be to rid
ourselves of most of what is unique and creative about individuals.
But in our universe there is no free lunch. The benefit of mutation
comes at a price. Many mutations are bad and lead to vice and
incompetence. If you look at the big picture, I think you will see
that the good and evil in humanity are closely intertwined, and that
this is precisely what makes humankind so wondrous.
Transhumanists
argue that the human genome could simply be engineered like any other
technology, and thus could continue to change and evolve without
having to worry about mutation and selection. But such fantasies are
far-fetched on close inspection. The human genome is incredibly
complex, and it isn’t clear that anyone could hold the whole thing
in their head in order to design a new human. Most machines that we
make, including computers and cars, are far less complex than the
human body, but when we are designing new versions, it is always
necessary to built prototypes and test them to see if they will work.
Invariably they do not work except after a lot of testing and
redesigning. But nothing like this would be ethical for humans. We
would obviously not want to raise an entire human being as a
“prototype” to be destroyed if he or she does not function
properly.
As a matter of fact, it is no more
possible to calculate the functionality of a new technology before it
is built and implemented, than it is to calculate the fitness of a
given organism. Any engineer will tell you this. It would appear that
human invention depends on selection as essentially as biological
evolution does.