New Dimensions of Population Growth

Professor Shannon teaches in the Economics Department, Clemson University.

A chart in the January 1982 issue of Reader’s Digest predicts an explosive growth in the world’s population.[1] Are we in dire danger of over-populating the world and causing widespread famine?

It all depends on how you look at things.

About a hundred years ago, an Englishman named Edwin Abbott wrote a book called Flatland. In it he depicts a two-dimensional world populated by lines, triangles, squares, other polygonal figures, and circles.[2]

In a thoroughly charming manner, Abbott explains how the Flat-landers organized society (those with more sides had greater rank), how they recognized each other (sometimes by feeling), and how they built their homes (with narrow entrances for the women, who were all straight lines and could readily damage other members of society).

What Abbott’s imaginative book clearly shows is that the assumptions we make about society have a great deal to do with the sort of future we can predict. That certainly holds true for the problem of population growth.

In his recent book, The Ultimate Resource, economist Julian Simon presents data that cast severe doubt on the likelihood that the presently rapid growth of population will continue. At least twice in history—once when men first began to use tools, and again about 10,000 years ago, when they started to farm—population grew very rapidly, only to taper off and grow at a much slower rate.[3]

But what if the present trend does continue? How will we feed and clothe ourselves—not to mention providing homes and energy?

Again, the outcome depends squarely on how we look at things—what assumptions we make about mankind’s ability to produce as well as to reproduce.

Consider a family sitting down to share an apple pie. If another person arrives to join them, there will clearly be less for those who got there first. Such a view as this lies implicitly behind the thinking of all those people who urge drastic birth control measures.

But that view ignores the productive potential of new members of society. After all, can’t they add to the world’s output of goods and services?

Can we, though, anticipate that they will add a proportional amount? Two hundred years ago, Thomas Malthus predicted that they would not.[4] Thus was applied the famous “law of diminishing returns” which still plagues the thinking of people who fear rapid population growth.

Malthus’s prophecy, however, did not come true. Instead of living standards falling as population increased, they have gone up. As Julian Simon and others suggest, there are several important reasons why this has happened.

One is the advantage of division of labor which Adam Smith described. It enormously enhances our ability to produce.[5]

Moreover, denser population makes both transportation and communication easier. Simon points by way of example to the agonizing difficulties of transporting food in early America; he also quotes one source as noting that “it was cheaper to move a ton of iron across the Atlantic than to carry it ten miles through Pennsylvania.”[6]

Most importantly, Simon argues, the growth of population simply means there will be more people to enjoy what life has to offer and to conceive of dramatic new ways to deal with our problems.

In Abbott’s fanciful book, one of the residents of Flatland takes an excursion into the world of three dimensions. Thus the book can be used—as Carl Sagan employed it for his TV series “Cosmos”—as a device to provoke us into trying to imagine what a fourth dimension must be like.[7]

So, too, with the matter of population growth. We must not allow ourselves to become trapped into thinking solely in terms of a future whose dimensions are limited.

Over the long run, Simon notes, resource costs have steadily fallen as man has used his creative wit to contrive new means of coping with scarcity. He sees scarcity, in fact, not as a formidable barrier but rather as an exciting challenge.

Simon has left behind the flatland of the folk who despair at population growth. In his hopeful vision, “the ultimate resource is people—skilled, spirited, and hopeful people who will exert their wills and imaginations for their own benefit, and so, inevitably, for the benefit of us all.”[8] []


1.   John Noble Wilford, “The People Boom Off the Chart!” Reader’s Digest, January 1982, pp. 114-15.

2.   Edwin A. Abbott, Flatland: A Romance of Many Dimensions (6th ed.; New York: Dover Publications, 1952).

3.   Julian Simon, The Ultimate Resource (Princeton: Princeton University Press, 1981), pp. 161ff.

4.   T. R. Malthus, An Essay on Population (New York: E. P. Dutton & Co., 1958), Book I, Chapter I.

5.   Adam Smith, An Inquiry into the Nature and Causes of the Wealth of Nations (New York: Modern Library, 1937), Book I, Chapter I.

6.   Simon, p. 191.

7.   Carl Sagan, Cosmos (New York: Random House, 1980), pp. 262-63.

8.   Simon, p. 348.