© Inter-Research 2001
ETHICS IN SCIENCE AND ENVIRONMENTAL POLITICS
2001, 9–18 Published January 23
Resale or republication not permitted without written consent of the publisher
Carrying capacity: the tradition and policy
implications of limits
Virginia Deane Abernethy*
Vanderbilt University School of Medicine, 209 Oxford House, Nashville, Tennessee 37232-4245, USA
KEY WORDS: Carrying capacity · Population · Environment · Limits · Ethics · World-views
ABSTRACT: Within just the last few centuries, science and technology have enlarged human capabilities and population size until humans now take, for their own use, nearly half of the Earth’s net terrestrial primary production. An ethical perspective suggests that potentials to alter, or further increase, humanity’s use of global resources should be scrutinized through the lenses of self-interested foresightedness and respect for non-human life. Without overtly invoking ethics, studies of the carrying capacity achieve just this objective. Carrying capacity is an ecological concept that expresses the relationship between a population and the natural environment on which it depends for ongoing sustenance. Carrying capacity assumes limits on the number of individuals that can be
supported at a given level of consumption without degrading the environment and, therefore, reducing future carrying capacity. That is, carrying capacity addresses long-term sustainability. Worldviews differ in the importance accorded to the carrying capacity concept. This paper addresses three world-views – ecological, romantic, and entrepreneurial – and explores the ethics and the policy
implications of their contrasting perspectives.
Environmental carrying capacity is a venerable, if
hypothetical, ecological concept that has acquired
fresh currency in light of the growing human population.
It relates individuals to quantity of resources and
quality of life, so it implies limits.
Familiar to stock-growers – year in and year out, for
example, it takes 30 acres to support a cow-calf unit on
typical Wyoming range-land – the concept of carrying
capacity in the modern context refers to the number of
humans who can be supported without degrading the
natural, cultural and social environment. Exceeding
the human carrying capacity implies impairing the
environment’s ability to sustain the desired quality of
life over the long term. The appropriate comparison is
to a too-dense cattle herd that finds sufficient feed for
several years, but at the cost of over-grazing so that the
land’s future yield is reduced to below the original
The concept of carrying capacity is widely discounted,
in part because it is fluid and virtually
unquantifiable. Past discoveries and technological
breakthroughs have, many times, raised carrying
capacity, and much western science encourages the
belief that technology’s potential is unlimited. Technological
optimists typically reject scientific warnings
that no substitutes exist for topsoil, fresh water, clean
air, and the "free services” of many species, or that
technology and its deployment to replace existing uses
of petrochemical energy will take 20 years to bring on
line, minimum. The standard answer to evidence that a
non-renewable resource is being depleted, or a renewable
one degraded, is that, if a resource becomes
"scarce” or pollution too detrimental, prices will rise
sufficiently to call forth either substitutes or innovative
technology that overcomes the problem. Technology
and market mechanisms, it is said, will always enable
humans to overcome putative natural limits.
Economic cornucopians point to low (even falling)
prices for essential commodities and staples, arguing
that they give no sign of impending scarcity. Economic
pricing theory is conveniently ignored, although this
suggests that a purely competitive market – which
describes many agricultural sectors - as opposed to a
monopolistic market often induces producers to go on
producing regardless of price signals. Pure competition
may, indeed, promote increased production as a
strategy for maintaining a constant income stream in
the face of declining prices.
Oil production in the late 1990s, when a barrel of oil
was priced at approximately $10.00, exemplifies the
price and production effects of relatively pure competition
even when the resource in question is actually
limited. Producer countries in the mid-East are dependent
on oil revenues to maintain the various consumer
subsidies to which their populations have become
accustomed. In the face of low prices, production
surged in order to maintain the needed revenue. Only
when the Organization of Petroleum Exporting Countries
(OPEC) re-exerted production caps did prices
rise. The leaders and the citizenry of industrialized
countries seldom interpret the higher price of oil or
natural gas as a sign of scarcity. Many remain convinced
that prices are arbitrarily manipulated. The production
quotas set by oil producing countries are not
seen as sensible responses that have much to do with
knowledge about the limited quantity of the underlying
Mixed evidence often leads to rejecting the concept
of carrying capacity, possibly because it is reassuring –
inherently more pleasing - to believe that humanity
has escaped from limits that constrain the growth of all
other species. Moreover, much in western history warrants
such confidence. For example, in the last decades
of the nineteenth century, just as the United States’
eastern forests were about depleted, crude oil was discovered
and put to multiple uses formerly met by wood
Ecologists, partisans in the ongoing debate, not only
assert that limits to essential resources and the threat
of both local and global pollution are apparent already,
but also warn of a threshold effect. They point out that
a boundary condition can be encountered suddenly.
Simplistically, a person jumping off a forty-story building
might enjoy the ride until brought up short by the
landing. A standard requiring total certainty - such as
the landing - carries a risk. This risk is that proof of the
carrying capacity’s being exceeded may come only
after much damage – and perhaps irretrievable damage
– has been done.
If optimistic forecasts are wrong and a natural
threshold is crossed, the consequence could be calamitous.
Nevertheless, proof sufficient to convince skeptics
remains elusive. Many experts and opinion-makers
contend that most difficulties are temporary,
requiring only the right fix. The inexactness of carrying
capacity models encourages that perspective. An
exact limit for a local population is rarely if ever established.
Yet, population studies in human and other animal
populations repeatedly show that exceeding this
uncertain limit, the carrying capacity, results in catastrophic
change. When do problems start to be seen as
intractable? When does the perceived cost of being
wrong about unlimited technological potential outweigh
the perceived cost of being wrong about limits
where none, in fact, exist?
Realms of disagreement
Disagreement about the theoretical validity of conceptualizing
and estimating ecological limits, and its
practical ramifications, is only the beginning. Attitudes
toward limits can be expressed in different realms,
becoming virtually an existential issue. One major
philosophical tradition denies limits to humanity’s
moral capacity. The divergence in schools of thought
reaches into policy.
In mid-eighteenth century France, controversy over
limits hinged on human moral capabilities. Francois-
Marie Arouet de Voltaire dramatized the conflict of
worldviews in Candide. Early in the plot, a trusting
Pangloss confidently reassures Candide that they are
living in the best of all possible worlds. Ultimately, a
world-worn and soberer duo settle for improving their
own backyard, "Cultiver son propre jardin.”
Opposed to Voltaire’s eighteenth century rationalist
view were the romanticists Jean Jacques Rousseau
and Condorcet in France and William Godwin, father
of Mary Shelley, in England. Central to their belief was
the imagining – untroubled by modern archeology - of
the uncorrupted "noble savage” of the Americas,
which ostensibly proved to their satisfaction the
(re)perfectibility of man and of society in the context of
living harmoniously with nature.
The eighteenth and nineteenth century controversy
about physical limitations was concerned less with
absolutes than with the balance between population
and resources. A maelstrom swirled around Thomas
Robert Malthus, whose famous first edition of his essay
on population was published on June 7, 1798. Malthus
argued that most humans would reproduce up to, or
even surpass, the limit of resources available to them.
Abernethy: Carrying capacity
The Malthusian observation invites the conclusion
that most people find sustained prosperity elusive,
because technological progress or other addition to
wealth stimulates population growth. This growth
eventually restores the original ratio of resources to
Malthus is remembered for the elegance and force of
his argument; however, the essential element of his
thought had been anticipated. Writes ecologist Garrett
Hardin, "Two thousand years ago Koheleth, the
Preacher, said in Ecclesiastes 5:11: ‘When goods
increase those who eat them increase.’” Similarly, "the
English philosopher David Hume, in 1752, played a
variation on the theme in Ecclesiastes: ‘Where there is
room for more people, they will always arise’” (Hardin
1998a). Malthus, a theologian and political scientist,
surely knew both sources.
THREE WORLD VIEWS
The conflicting worldviews on limits to both
resources and human moral capacities descend to the
present. The taxonomy proposed here identifies three
patterns and is admittedly an oversimplification. But a
division into ecological, entrepreneurial, and romanticist
traditions – loose classification though it is - may
partially illuminate present-day political and issue
coalitions that might otherwise seem mystifying.
The entrepreneurial tradition relies on individual initiative
and contractual relationships for the betterment
of mankind and society, and is mainly skeptical of the
moral perfectibility of human kind. In the tradition of
John Locke, it assumes that pursuit of private ends can
serve the common good because the incentive to
increase personal property often results increasing the
total wealth that a society may ultimately enjoy. Proponents
are pragmatists and, often, self-styled conservatives.
The dominant motive acknowledged in oneself and
generally attributed to others is not altruism but selfinterest,
- as in the Declaration of Independence’ guarantee
of the "pursuit of happiness” - which is taken to
be a virtually universal human characteristic that can
be socially channeled to become usually positive in
effect. Competitive self-interest reinforced by good
information and accountability is expected to yield a
well-regulated society, rational markets, prosperity
founded on market principles, and fair government.
The entrepreneur advocates free trade and ample
immigration so long as these policies appear to
enhance net profits. They rely not on perfecting
human moral instincts but, rather, on the social contract
for mutually-agreed governance.
The entrepreneur’s differential views of limits
depending upon their reference to moral or physical
realms suggest a pragmatic rather than ideological
foundation. Pragmatists are swayed by evidence.
Technological innovations that quadrupled carrying
capacity since the Malthusian era are the basis for the
entrepreneur’s skepticism that material limits are real
and close. A 1997 essay in The (London) Economist
points out that "predictions of ecological doom, including
recent ones, have such a terrible track record that
people should take them with a grain of salt.” The
essay continues, "…journalists and fame-seekers will
no doubt continue to peddle ecological catastrophes at
an undiminishing speed. These people, oddly, appear
to think that having been invariably wrong in the past
makes them more likely to be right in the future”
(Environmental Scares, 1997, p.19).
Reasonably enough, this essay appeals to the historical
record. Why would the future be different?
As the twentieth century closes, many entrepreneurs
accept the assumptions relating to technology
and the physical world that have been provided, in
large measure, by Julian Simon. This is the late University
of Maryland economist, author, and editor of
the rose-colored-wrapper compendium The State of
Humanity (1996) and pro-immigration tracts such as
Immigration: The Demographic and Economic Facts
Simon's premise is that limits to natural resources as
well as the environment's capacity to cope with pollution
invariably yield to the transformations made on
nature by technology. Thus, natural constraints are
merely challenges, ultimately irrelevant to the economy.
Technology will refresh or give us substitutes for
clean air and water, rich topsoil, cheap fossil fuels, and
Earth's services in detoxifying pollution. That is, manmade
capital can substitute for natural resources indefinitely
and without end; repeated doublings of the size
of the economy and population present only opportunity.
Whatever accelerates growth should be pursued.
In 1995, a Washington, D.C. think-tank, the Cato
Institute, published Simon's nigh-incredible cornucopian
assertion that "Technology exists now to produce
virtually inexhaustible quantities of just about all
the products made by nature.” Extending his foray
into the world of science, Simon writes, "We have in
our hands now -- actually in our libraries -- the technology
to feed, clothe and supply energy to an evergrowing
population for the next 7 billion years.... Even
if no new knowledge were ever gained... we would be
able to go on increasing our population forever...”
(Cato Institute 1995, p. 14).
ESEP 2001, 9–18
Note that 7 billion years ago was about two and a
half billion years before the first one-celled life form
appeared in Earth's newly formed primal ooze. Can
one have confidence in the author of prognostications
for 7 billion years into the future?
Physicist Albert A. Bartlett of the University of Colorado
is a gentleman inclined to give adversaries the
benefit of the doubt. Therefore, he was pleased to
report that Simon did not entirely mean what he wrote:
"Simon said that the ‘7 billion years’ was an error and
it should have been ‘7 million years.’” But, Bartlett
continues, "It is too early to breathe easily.” Given the
1996 world population of approximately 5.7 billion and
an annual population growth rate of 1 percent, world
population after 7 million years would be equal to 2.3 x
10 to the 30410th power. "This is a fairly large number!” (Bartlett
Non-mathematicians might like to know that 2.3 x
10 to the 12th power is 2.3 trillion (American definition of "trillion”).
So how large is a number with the exponent of not 12
The hard-line cornucopian view also has champions
in Dennis T. Avery of the Hudson Institute and author
of Saving the World with Pesticides and Plastic (1995),
and Thomas Lambert of the Center for the Study of
American Business (CSAB). Lambert writes that, "natural
resources are not limited in any meaningful
sense” because resources are really best understood as
services. It is, after all, "the particular services a material
provides -- not its physical composition -- that
makes a material a resource” (Lambert, 1996, p. 5).
While appealing in their reasonableness (unlike
Simon), Lambert's and Avery's visions deny the implications
of the environment’s being an envelope around
the economy. Yet, the environment provides inputs to
economic production, and the environment receives
not only the useful but also the waste products of economic
activity. As put by economist Herman Daly,
"The economy is a wholly-owned subsidiary of the
The ecology response to the cornucopian vision
Ecologists and certain economists - for example,
Daly (1990; 1991; Cobb and Daly, 1990) - point out that
technology can employ (or alter or discover) one
resource to make up for shortfalls in another, and use
assorted strategies to minimize pollution, but these
expedients only change the pressure point. One cannot
avoid the risk of shortfalls or bottlenecks developing
in the substitutes and during the transformation
process. Difficulty is compounded if the real world has
a propensity to develop problems in multiples, not one
at a time. In times of stress, anything that can go
wrong, might go wrong. How does technology cope
with the snowball effect? "With difficulty,” answers an
ecologist or old-fashioned conservative. And, "Why
take the risk?”
The energy constraint
Since mid-century (Cottrell, 1955), growing numbers
of scientists have tried to make the public aware that
the large increase in carrying capacity has been possible
only because of readily available fossil fuels, especially
oil. Walter Youngquist (1997), Colin Campbell,
L.F. Ivanhoe, Richard Duncan and others suggest that
a peak in oil production in the vicinity of 2005 to 2015
A.D. will be followed by steady decline. Natural gas is
expected to be plentiful for about 40 years after the
peak in oil production, and new processes are likely to
increase its versatility. Without fossil fuels, it would
probably be impossible to farm the vast acreage that
has made possible the present population size.
In November, 2000, geologist Richard Duncan addressed
a Geological Society of America "summit” held
in Reno, Nevada. Citing historical data, Duncan shows
that world energy production per capita grew by 3.45
percent annually between 1945 and 1973; growth
slowed to 0.64 percent annually from 1973 to 1979; then
growth ended and began to decline at the rate of 0.33
annually from 1979 to 1999. Fitting a mathematical
equation to data points on this curve, Duncan derives
projections which suggest that, by 2030, energy production
per capita will fall back to its 1930 value. This
scenario envisions rolling, then permanent, blackouts
of high-voltage electric power networks, worldwide.
Industry geologists are sanguine regarding the
quantity and substitution possibilities for natural gas
and other energy sources and do not yet state publicly
that a peak in oil production is imminent. Nevertheless,
more pessimistic forecasts are gaining ground
(Banks 1998), and the Paris-based International
Energy Agency (IEA) of the Organization for Economic
Cooperation and Development (OECD) stated in 1998,
for the first time, that "the peak of world oil production
is in sight” (Kerr 1998). Were the majority to adopt the
views of Campbell and others, entrepreneurial
assumptions about limits might be readily reversed.
The habit of inductive reasoning makes entrepreneurs
open to new perspectives. Sustained sharp price
increases for essential commodities, rising public costs
(higher taxes) associated with a rapidly growing population,
and fees for the formerly-free services of nature
Abernethy: Carrying capacity
would be persuasive to those of the entrepreneurial
bent. Many who reject ecological statistics would be
weaned from the conviction that wealth is both abundant
and renewable by market and financial signals.
Contrasting with the pragmatism of the entrepreneurial
sector, the romanticist tradition appears to be
driven by ideology. Denying limits in all realms,
romanticists assert an unlimited human moral capacity
to do right. While conceding that some people go
wrong, romanticists explain that humans are not
expected to reach their full moral potential under
impoverished or mean social conditions.
The development of true altruism – not mere reciprocal
altruism – is the highest moral trait in the
romantic pantheon, but it requires nurturing love and
a sufficiency of goods. Thus, the theoretical perfectibility
of humanity and human society carries a
caveat regarding requirements for a supportive social
and economic milieu. These presumptions are the
source of advocacy for social reform and government
regulation aimed at redistributing wealth in order to
Given that it is society’s obligation to rehabilitate the
less fortunate so that every potential for human perfectibility
is actualized, it becomes axiomatic, for
romanticists, that society can do it. The means exist.
Romanticists trust that nature can provide without limit
because, if the goal that all humans should have access
to sufficient resources is to be realized, that is clearly
In the romanticist formulation, therefore, the ecologists’
concept of carrying capacity is irrelevant, if not
malevolent, because it sets an upper limit to the
resources that ever can become available to humanity.
Lest moral potentials not be fulfilled, social reformers
are constrained to believe in boundless wealth that
need only be equitably distributed in order to create
the perfect society.
Independently, Garret Hardin has arrived at a similar
analysis of the romanticist worldview. He cites in
evidence Karl Marx’s unprovoked ad hominem attacks
on Malthus (in the vein of "‘superficial,’ ‘a professional
plagiarist’”). Hardin suggests that "a single overarching
view accounts for these and many other invectives
put forward by Marxists and liberals during the past
century and a half: this is their tightly held denial of
limits in the supply of terrestrial resources. Friedrich
Engels, Marx’s collaborator and financial supporter,
asserted baldly that ‘The productivity of the land can
be infinitely increased by the application of capital,
labour (sic), and science’” (Hardin 1998b, p.182).
The romanticist tradition is manifest in modern times
among those who strive to advance internationalist and
collectivist agendas. They believe in breaking down
national boundaries because nation-states perpetuate
disparities in wealth. University of Chicago professor
Martha Nussbaum exemplifies the tradition in her
teaching that "the concept of national citizenship is too
exclusive and ‘morally dangerous.’ Justice and equality,
she claims, require ‘allegiance to the worldwide
community of human beings’” (Erasing Self-Rule 1998,
p.16). Romanticists support behavior and international
institutions that tend to erode sovereignty.
Some who appear to favor world government try to
deflect objections by asserting its inevitability. Joe De
Courcy observes that, "On 17 February 1930, for
instance, a leading member of the Council on Foreign
Relations, James P. Warburg, told a U.S. Senate Committee:
‘We shall have world government whether we
like it or not...by consent or by conquest.’ In 1976, Professor
Saul Mendlovitz, director of the World Order
Models Project, said there is ‘…no longer a question of
whether or not there will be a world government by
the year 2000.’” The stealth strategy is preferred by
former Senator Alan Cranston (D–California), past
president of United World Federalists. He "told Transition,
a publication of the Institute for World Order, that:
‘The more talk about world government, the less
chance of achieving it, because it frightens people who
would accept the concept of world laws’” (de Courcy
1998, pp. 34-35).
The ecological tradition is in almost all respects the
opposite of the romantic-internationalist. Ecologists
are strongly influenced by biology and many emerge
from this academic discipline. Their views are formed
from observation of natural systems, including behavior;
that is, their method of reasoning is inductive, like
the entrepreneur, although the two traditions attend to
different data sets.
Ecologists accept the concept of carrying capacity as
essentially self-evident. The Earth is round and finite;
so, therefore, must be its resources and its capacity to
cope with pollution (Bartlett, 1996; Pimentel and
Pimentel 1991; 1996). Further, they see the imminence
of carrying capacity limits in the deterioration of countless
natural systems. Signs include the 15 out of 17
world fisheries that have crashed; falling water tables
in aquifers; topsoil loss; annual oil production greater
ESEP 2001, 9–18
than discoveries (therefore, declining real reserves);
mass extinction of species; and compromised capacity
to cope with atmospheric and water pollution
(Pimentel and Pimentel 1996; 1997).
Carrying capacity has greatest relevance to policy
when viewed in local terms, because it often is not possible
to affect the destiny of units larger than the local
community or, at the outside limit, the nation. Information
about the environment, including resources
and vulnerabilities, is often best at regional or smaller
levels. Further, cooperation is more easily mobilized at
the neighborhood, state, or at least national level
because it often depends upon kinship or friendship –
a sense of identity and shared interests that facilitates
the exchange of favors over periods sometimes longer
than a generation. In addition, the presence of a competitor
is an incentive to cooperate. Communities that
are vying with an opponent will be more likely to cooperate
internally, but this motive cannot coexist with the
ethos that all belong to one world.
Finally, ecologists apply the lesson of the "tragedy of
the commons.” In 1968 Garrett Hardin illuminated the
essential characteristic of a commons, defining it as a
resource from which no one can be excluded. Everyone
has access to a commons.
The fact of universal access has major implications
for the motivation to conserve because conservation
depends upon self-restraint, saving a resource in order
to enjoy or use it in the future. No one has the incentive
to conserve a resource to which no one can be denied
access, for the reason that those making the effort, or
their descendants, are very unlikely to have much of
the future benefit from their present sacrifices.
In a commons, in fact, the better individual strategy
is to use the resource as intensively and fast as one can.
The maxim is, "Use it or lose it,” with a vengeance.
Organizations with the appearance of a commons
have successfully conserved or even improved a
resource, at times. But delving deeper into instances of
this type invariably reveals a mechanism for excluding
users. This holds true whether the resource is a forest,
a fishing ground, or a village green for pasturing
sheep. Informal mechanisms for regulating use can be
effective, if often rough on transgressors, and the gradient
of penalty may escalate. But regulation that lacks
enforceable and meaningful sanctions is unlikely to
protect a resource (Leal 1998; Ruttan 1998).
Thus, the moral hazard of the commons is the ultimate,
logical reason why one-world, a world without borders,
will not get one very far into a peaceful and prosperous
future. If no person, and no community or country, can
say, "Keep out; it’s mine,” then no one and no region or
country has the incentive to conserve. And that, simply,
is because there is almost no realistic hope of future benefit
in proportion to one’s effort and self-restraint.
Ecologists tend to conclude that the physical capabilities
of Earth and the moral capabilities of mankind are
equally constrained by natural law. Humans are not so
unlike other species that the principles of evolutionary
biology would not apply to human behavior (Trivers
1971; Dawkins 1976; Wilson 1975). Survival and reproduction
of one’s genes is the de facto evolutionary test
of success. Inevitably, behavior is shaped to increase
the probability of survival.
By extension, moral codes are subject to the possibilities
inherent in a physically-limited Earth. Ecologists
take into account that humans are not generally altruistic,
because altruism like other behavioral traits is to
some extent heritable, and altruists are less likely than
others to leave offspring (Hamilton 1964; Trivers 1971;
Wilson 1975). Behavior and culture that lead to extinction
of those who practice them cannot be moral, by
definition. For example, if wastefulness in use of
resources leads to extinction, then it cannot be moral.
Nor can altruism including the sharing of resources, if
it leads to extinction, be moral (Elliott 1997).
Altruism is particularly self-destructive when
applied internationally. Those who advocate altruism
must necessarily believe that nature is a cornucopia of
Accepting limits in principle and in fact, ecologists
advocate not only prudence in use of resources but
also discovery of motives which induce intrinsically
self-interested humans to conserve. Thus, the moral
hazard of the commons is the ultimate, logical reason
why one-world, a world without borders, will not get
one very far into a peaceful and prosperous future.
If no person, and no region or country, can say,
"Keep out; it’s mine,” then no one and no community
or country has the incentive to conserve. And that, simply,
is because there is almost no realistic hope of
future benefit in proportion to one’s effort and selfrestraint.
To sum up the ecologist perspective, given the probability
of coming scarcity, a multiplicity of logistic
problems in increasing efficiency, and the realities of
human nature - including political and ethnic loyalties
- many ecologists suspect that the only practicable
solutions to most environmental problems will be local.
A COLLISION OF WORLDVIEWS
The romanticist assumption that humankind and
society are potentially perfectible, needing for fulfillment
only that the planet’s abundant resources should
be equitably distributed, entails a surprising array of
corollary axioms. The heirs of Rousseau and Marx
Abernethy: Carrying capacity
advocate a world without borders, one-world. They
reject the competitive efforts of one country or region
to thrive beyond the realistic aspirations of any other.
They espouse submerging national interests.
Applied to the United States, the one-world ideology
is expressed in advocacy for reducing consumption to
the average of world levels (substantially lower than
present European levels of consumption) and for open
borders. Part of the rationale for the latter goal is that
the United States is unlike any other nation. It is a
nation of immigrants having no history of a citizenry
who feel united as a people, and therefore it has no
legitimate territorial integrity. In short, the United
States is not a nation-state like other countries of the
world but is, rather, "an idea,” appropriately stripped
In the cultural and social realms, this description of
America justifies accelerated immigration of peoples
as unlike to existing Americans as possible, and advocacy
of multiculturalism. Already a feature of public
school (embodied in new, government-sponsored history
standards) and many private school curricula,
multiculturalism teaches that all cultures are equally
relevant to America. Remarkably (and illogically
within the terms of multiculturalism’s own worldview)
one culture is presented as illegitimate – destined to be
overcome by others. That is the culture of the Founders
based on European and particularly Anglo-Saxon principles
of ethics, government, religion, and Euro-American
Others think differently on each of these dimensions.
Whether it be the legitimacy of the nation, the sense of
patriotism and kinship in being American, the inviolability
of carrying capacity if the nation is to survive, or
the means of protecting carrying capacity, ecologists
begin from different premises and arrive at vastly different
In addition, ecologists and entrepreneurs are converging
on the view that humans are not altruists - the
opposite of the romanticist credo. A factual basis for
rejecting the myth of the "noble savage” is well developed.
The current view is that altruism manifested in a
conservation ethic is no more present in traditional
than modern society (Williams 1966; Ruttan 1998).
Inductive reasoning is common to both ecologists
and entrepreneurs but, focusing on different data, they
arrive at different conclusions. At present, entrepreneurs
assert that the greatest good derives from free
trade and minimal impediments to the movement of
labor. Attentive to natural systems, ecologists reach a
conclusion – one also having policy implications – that
is based on the limits of nature in general, and of
human nature in particular.
It seems likely that the majority of ecologists and
entrepreneurs (with the exception of multinational corporations)
assume that the United States is a nationstate,
like others, with territorial integrity and its own
culture. Culture is taken to mean the values and
assumptions, history, language, and technology that
are largely shared by all members of the society. The
government has its primary responsibility to the
nation, the United States, and a corollary obligation to
protect the nation’s people, all Americans. It would not
put the matter too strongly to assert that the government
of the United States is obliged to put the wellbeing
of Americans above all others, just as the governments
of all other countries are expected to do for their
Preservation of carrying capacity, which is inherently
limited, is fundamental for the present and future
wellbeing of any nation. Over-taxing the carrying
capacity destroys, sometimes irremediably, the longterm
ability of the resource base to sustain those who
depend on it.
Population growth indubitably increases the pressure
on the environment - even romanticists admit this
so long as their focus is the rest of the world rather than
the United States (see, for example, the former Vice-
President Albert Gore’s Earth in the Balance ).
Concern about U.S. population growth pushes ecologists
to protest present U.S. immigration policy which
allows the addition of over1 million persons annually
(net of emigration), as well as the subsequent growth
from descendants of current immigrants. Immigration
and the children of post-1970 immigrant families,
together, accounted for over 70 percent of U.S. population
growth in the decade of the 1990s (Camarota
1999). That share rises continuously as the stock of
recent immigrants and their descendents grows and
the native-born fertility rate remains low.
Ecologists see not only the direct threat to carrying
capacity from increasing population size through
immigration, but also the indirect effect arising from
immigration’s effect on the incentive system. Americans
are disposed to conserve land that they own or
control, to stabilize population through self-restraint in
childbearing (the native-born fertility rate is below
replacement level), to tax themselves for environmental
rehabilitation efforts, and to mitigate ongoing environmental
destruction. However, immigration makes
the United States into an effective "commons,” a condition
conducive to using resources as fast as possible
lest one lose out on one’s share.
A rational person who sees no prospect of stabilizing
population so long as immigration continues might
well resist any sacrifice made on behalf of the environment
or society at large (Abernethy, 1993). If efforts to
protect the carrying capacity are doomed to fail, anyway,
because of continuing population growth, why
conserve, why do without today, why support an envi-
ESEP 2001, 9–18
ronmental ethic? A case in point, to protest continuing
immigration, some Californians responded to wateruse
restrictions during the 1980s drought with the
bumper sticker, "Flush Twice.”
Unless reasonably assured that present and future
benefit will accrue to themselves or their posterity, few
persons will forego present consumption or childbearing
for the purpose of conserving the environment.
This means that Americans’ incentive to conserve the
environment can probably be maintained only by
offering hope that their efforts will not be in vain. Ecologists
conclude that reducing immigration to the number
compatible with stabilizing population size, or
even allowing population decline should that prove
necessary, is the only sustainable course.
A POLICY COLLISION
Translating worldviews into policy initiatives, partisans
of the three distinct traditions find themselves
joined in surprising coalitions. When the focus is on
protecting a particular resource (a forest, a river, public
lands), romanticists work together with ecologists.
Romanticists and entrepreneurs (who desire access to
the cheaper world labor market without moving production
operations abroad) readily work together to
defeat legislation that would reduce immigration numbers
to a level compatible with U.S. population stabilization.
An instance of the serendipitous romanticist-entrepreneurial
coalition was their mobilization to block a
proposed reduction in numbers of legal immigrants in
spring, 1996. The pro-immigration National Immigration
Forum headed by Frank Sharry and the liberal
Urban League as well as the National Association of
Manufacturers and the National Trial Lawyers Association
argued in concert - and successfully - for continuing
high levels of legal immigration (Davidson 1995,
p. 34; Chavez 1996; Levine 1996; Jacobs 1995; Freedburg
1996; Tech Firms 1996). However, this coalition
fragments on conservation issues.
Divisions can be found within the entrepreneurial
community itself. For example, Fred Charles Iklé, himself
a conservative, takes neo-conservatives to task for
their idealization of non-stop economic and population
growth: "The fabulous success of conservative economic
policies has seduced many in our midst into taking
economic growth as the defining attribute of conservatism.
These brethren now believe that...good
growth can and must continue indefinitely. They act
as if conservative thought were nothing but the philosophy
of perpetual growth” (Iklé 1994, p. 36).
Warning against immigration-driven growth, conservatives
might cite Lester Thurow, former Dean of
MIT's Sloane School of Business Administration, who
postulates that "No country can become rich without a
century of good economic performance and a century
of very slow population growth” (cited in Lind 1995). In
other contexts, Paul Krugman (1994) observes that
"Economic growth that is based on expansion of
inputs, rather than on growth in output per unit of
input, is inevitably subject to diminishing returns.”
Robert Stein in Investors Business Daily, states that
immigration dilutes the amount of capital available per
job and thus undercuts the mechanism for raising labor
productivity and non-inflationary wage increases
Ecologists attempt to appeal to the business community
by pointing out that population growth makes
more environmental regulation necessary and adds
dramatically to the fiscal burden of local and state government.
The more general arguments, that population
growth threatens the carrying capacity, and immigration
depresses the wages of American labor (very
often the least skilled, already disadvantaged, are hurt
most) seem more attuned to classical liberal thinking.
The competing rationales and outcomes appear reasonable
or not depending upon one’s perspective.
Entrepreneurs hear restrictions on immigration as
interference with free markets and the economies of
low-wage labor – although an imported labor force displaces
Americans who may then go on the public dole.
Moreover, low-skill immigrants and their families are
very likely to depend on public assistance (especially
during months of slack employment), lack health care
insurance, and have children who are educated at
public expense (Matloff 1998; Huddle 1998). Calls for
government programs to correct poverty are an almost
inevitable result of importing poverty.
The radical-left element of the romanticist school
hears immigration restriction as racist (Political Ecology
Group 1998). Racism is inferred because reduced
immigration would inevitably cut most from the largest
streams of immigrants, which are from the third world
and the former USSR. Further, one-world romanticists
cast the attempt to conserve a unique American culture
as illegitimate - although all nations, as a matter of
course, intend to conserve their own language, history,
traditions, and values. The charge of "racism” has successfully
intimidated large numbers of Americans
whose goals are conservationist and certainly not
racist. I observe that the term, "Nazism,” is being substituted
as "racism” loses credibility and punch.
Conservationists place a high priority on the quality
of life in their communities, and their goals encompass
preserving good opportunity for coming generations of
Americans. Most Americans look to the future. In the
present, wishing to protect American workers from
having their wages competed down to third world
Abernethy: Carrying capacity
standards, citizens seek a healthful, open environment
and minimization of government intrusion into their
lives. The majority sees no need to reject the traditional
culture, which is not only their birthright but also
the safeguard of democratic government and Constitutionally
Every country has its interests and its culture. The
culture evolves from within as most citizens wish it to
do. Such has been the course of history. In a healthful
state, the culture promotes a rate of growth, or stasis,
where the natural environment sustainably supports
the associated society at a level that is expected and
acceptable to its citizens.
But romanticists deny the importance of both limits
and western culture and, for the sake of a one-world,
internationalist chimera in which everyone is equal,
would see everyone poor. This cannot be right. The
moral high ground must have a basis in environmental
and human possibilities. Disrespect for the carrying
capacity is destabilizing. It exacts, ultimately, a devastating
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Editorial responsibility: John Cairns Jr.,
Blacksburg, Virginia, USA
Manuscript (ms) accepted by editor: Jan 16, 2001
MS received at Headquarters: Jan 21, 2001
MS published on the web: Jan 23, 2001