The Tragedy of the Commons
American Ecologist and Microbiologist
Concerned with overpopulation
Pro-population control by government
“The Tragedy of the Commons”
Published in Science magazine 1968
Had four children
Committed suicide together with his wife when he was 88 (she was 81)
Problems with no technical solution
Some problems cannot be solved with science, e.g. the arms race.
Overpopulation and competition for resources is this kind of
Since no technical solution, the solution must be political.
Thomas Malthus (1766-1834, English
Population grows exponentially, food
supply can only increase
arithmetically, so eventually we will
starve (or decrease population via
wars, disease or anarchy)
Commons: common land available to all for grazing animals, gathering
Tragedy of the commons: every farmer will tend to maximize their own
profits by increasing their herd or increasing their gathering of
resources without regard to the long-term depletion of the land.
This is rational because the benefit to the individual farmer (of, for
example, grazing one more animal on the commons) is larger than
that farmer’s share of the overall depletion of the shared resource
(i.e. the commons).
Historical commons: not really a free-for-all. Not public land. Only
small number of farmers had inherited limited bundles of rights,
numbers of animals were limited.
The New Commons
The tragedy of the commons is a metaphor for anything held in
common, used by all freely and not regulated.
Everyone will maximize his own benefit to the detriment of the whole.
Modern “commons” include:
The sea -- overfishing
The air, the land, rivers -- pollution
The public noise level -- sound pollution
National parks – overuse
The earth itself (energy, food supply, living standards) --
Hardin’s main concern.
“Freedom to breed is intolerable”
Overpopulation harms the world as a whole. The more
people there are, the fewer resources there are available to each person.
As long as we have a welfare state, people will continue to have more
children than is good for society. Rational agents maximize their own good
(more children), when the cost to them is relatively low because the cost
is shared in common with society as a whole.
Assumption: each child is a net good to its parents but a net bad to society.
“Has any cultural group solved this practical problem at the present time,
even on an intuitive level? One simple fact proves that none has: there is
no prosperous population in the world today that has, and has had for
some time, a growth rate of zero.”
New Developments in World Population
Hardin’s work written in 1968. Since then:
China’s one-child policy
Nearly one hundred countries now have a fertility rate below replacement level,
including the United Kingdom, France, Italy, Germany, Vietnam, Brazil,, Cuba,
Kazakhstan, Brunei, Russia, Japan, China, Thailand, Macao and Hong Kong.
Hong Kong is the lowest at .98 children per woman.
“… the most rapidly growing populations on earth today are (in general) the most
Countries with the highest fertility rates: Mali, Niger, Uganda, Somalia, Afganistan,
Yemen, Burundi, Burkina Faso, the Congo, Angola, Sierra Leone (all over 6
children per woman)
The demographic economic paradox.
Hardin: appeals to individual conscience are bad because:
1) It discriminates against people of good conscience, and tends to
eliminate them from the population.
2) It won’t work in the long run. Nature’s revenge. People without
conscience with outbreed the others, and population will increase
3) It is not psychologically healthy to force people to act against their
own interests on the basis of conscience.
So the only choice is “mutual coercion mutually agreed upon”
Freedom must be limited.
Mutual Coercion Mutually Agreed Upon
Mutual coercion to solve population problem (government regulation
on number of offspring allowed) and other problems of the
Enclose the commons as private property,
Or limit usage of the commons (e.g. limits on people’s right to pollute,
to fish on the high seas, to increase public noise levels, etc.)
Quotes Hegel (Engels): “Freedom is the recognition of necessity”
Rights and freedoms must be restricted for the good of everyone.
The right to breed in excess is like the right to steal from banks – it
must be controlled.
Questions for discussion
Is what Hardin advocates fascism?
Is it justified? Is it necessary?
Is China’s one-child policy justified?
Why have birth rates fallen in the developed world (and much of the
Why is it so low in Hong Kong?
Is it conscience?
Is relying on conscience/voluntary restriction of anti-social behavior self-
defeating in the long run?
Is the Hong Kong government right to try to persuade people to have at least
Naess, Arne, (1983) “The Deep Ecological Movement: Some Philosophical
Aspects,” in Environmental Philosophy, p. 193-211, on handout
Des Jardins, Environmental Ethics, Chapter 10, “Deep Ecology” p. 210-231, on
Des Jardins, Environmental Ethics, Chapter 7, “Biocentric Ethics and the Inherent
Value of LIfe” p. 128-151, on reserve in Philosophy Dept.
Berry, Thomas, “The Viable Human”, ,” in Environmental Philosophy, p. 171-181,
on reserve in Philosophy Dept.