This text was adapted by The Saylor Foundation under a Creative Commons Attribution-NonCommercial-ShareAlike 0 License without attribution as requested by the work’s original creator or licensee. Preface

Views of Population Growth

Thomas Malthus, an English economist who lived about two hundred years ago, wrote that population increases geometrically while food production increases only arithmetically. These understandings led him to predict mass starvation.

Source: http://commons.wikimedia.org/wiki/File:Thomas_Robert_Malthus.jpg.
The numbers just discussed show that the size of the United States and world populations has increased tremendously in just a few centuries. Not surprisingly, people during this time have worried about population growth and specifically overpopulation. One of the first to warn about population growth was Thomas Malthus (1766–1834), an English economist, who said that population increases geometrically (2, 4, 8, 16, 32, 64, 128, 256, 512, 1024…). If you expand this list of numbers, you will see that they soon become overwhelmingly large in just a few more “generations.” Malthus (1798/1926) ^[9] said that food production increases only arithmetically (1, 2, 3, 4, 5, 6…) and thus could not hope to keep up with the population increase, and he predicted that mass starvation would be the dire result.

During the 1970s, population growth became a major issue in the United States and some other nations. Zero population growth, or ZPG, was a slogan often heard. There was much concern over the rapidly growing population in the United States and, especially, around the world, and there was fear that our “small planet” could not support massive increases in the number of people (Ehrlich, 1969). ^[10] Some of the most dire predictions of the time warned of serious food shortages by the end of the century.

Fortunately, Malthus and ZPG advocates were wrong to some degree. Although population levels have certainly soared, the projections in show the rate of increase is slowing. Among other factors, the development of more effective contraception, especially the birth control pill, has limited population growth in the industrial world and, increasingly, in poorer nations. Food production has also increased by a much greater amount than Malthus and ZPG advocates predicted.