1. Tragedy of the Commons and followup, both available at PapersAccessibleToStudents
  2. Is Limiting Population Growth a Key Factor in Protecting the Global Environment?, also available at PapersAccessibleToStudents
  3. ; see also other information on the site.


The population of the Earth is currently 6.8 billion people and growing at the rate of nearly 83 million/year ( It is projected to reach 9 billion by 2050, with most of the increase occurring in less developed countries. On one hand, people in these countries require fewer natural resources. On the other, they aspire to an increased standard of living, which requires increasing resources.

Some argue that we have already exceeded the carrying capacity of the Earth (e.g., Lester Brown); others (e.g., Stephen Moore) point to an intellectual tradition beginning with Thomas Malthus in 1798 that predicts mass starvation caused by the geometric increase in human population outstripping arithmetic increases in food production—over two centuries of crying wolf. The population in 1800 was roughly 1 billion. In 210 years it has increased sevenfold and the only episodes of mass starvation have been caused by political failures.

Prompt 1:

Suppose that in 2020, after Herculean effort, we solve the energy problem (maybe by harnessing fusion, or efficient solar production of liquid fuel, or…). What then would or should be the carrying capacity of the Earth? Write a short (2-page) essay with a proposed and suitably quantitative answer, citing appropriate sources.

Prompt 2:

With the impending retirement of the boomer generation, the inevitable proposals to impose a means test on Social Security are tempting lawmakers. After all, why should the government be sending checks to those who are comfortable and financially independent when millions of children lack food security? Others counter that imposing a means test rewards those who have squandered their income on big-screen TVs and other luxuries, instead of saving responsibly for their later years. Why should we reward imprudent behavior?

In some measure the Social Security problem parallels the global population problem. Does the developed world owe food security to the underdeveloped world? Or does supporting burgeoning populations of people who cannot provide for themselves simply exacerbate the problem? Write a short (2-page) essay, citing appropriate sources.

Pick either prompt and submit your essay to me electronically by Friday, 2/11, at 5 pm.