Ever since Malthus most people have believed that increasing population slows or even reverses economic development. However in 1965 a young Danish economist wrote this small book questioning this orthodoxy. She showed that over most of history the effect of increasing population has been positive. Most serious demographers and economists now accept that she was right. It is tragic that the general public and population doomsayers have still not got the message, and persist in pushing family planning down the throats of the poor in the vain hope that it will help economic development. This book is a modern classic.

The theories associated with the Rev. Thomas Malthus have not had an easy time lately. Many social and natural scientists have increasingly scrutinized and become skeptical of the Malthusian model of population growth. His idea that the ever-present force of population to grow uncontrollably and that this growth will result in the diminishing returns of resources leading to famine and disaster jointly predict doom, seem to have fallen out of favor. Leading this anti-Malthusian charge is Ester Boserup, who since the 1960's has published a number of critiques of Malthus as well as setting up her own paradigm on population growth. Population and Technological Changes, which has been extensively reviewed, is an extension of her 1965 work, Conditions of Agricultural Growth, which she calls only a partial model. This critique will examine Boserup's main points that technology is necessary for population growth and vice-versa; as well as the major criticisms of that work. In her previous works, Boserup looked only at agricultural technologies and defended the thesis that population changes affect economic growth by looking at agricultural technologies. In Population and Technological Changes, she examines other population-linked technologies such as fallow systems, irrigation, the use of fertilizers and the crop yields. Although she does state that food-raising is still a principle focus, she also brings in other technologies that affect population. These include density, transport technologies and knowledge of agricultural methods as auxiliary factors to population growth. This work is set apart from others in the field since it goes against the conventional wisdom. It sets itself in opposition to many of the time-tested established theories. Boserup's main thesis is that substantial population size and moderate to high areal density have been and still are two necessary preconditions for technological development. She further says that they are semi-causal conditions for technological development through time. The book is organized into five parts, each of which represents a specific ecological problem and its effect on population. Part I sets the framework for the book by providing historical and cross-sectional data on population. Here she sets up categories of population level, density and agricultural production level which she later uses as the basis for comparing societies who are at different places in terms of their technologies and populations. One critique of this system is that not all high density/high population countries fit nicely into her model, where most of the high density/low technology countries do. This has led critics to infer that her model is not applicable in the modern world. The various types of agricultural systems are also explained, and agricultural productivity in relation to the five levels of technological proficiency she defines. Part II explores the population-technology link that was found in the ancient world. More historical data is added as she painstakingly goes through the major advances in ancient food production technologies. The change of field fallowing periods and the differing methods of clearing fields such as slash and burn or terracing are all different stages of this change. This run-through the basics methods discussed in Human Ecology is a dry but necessary step, which many other population ecologists have failed to do. She notes that with the shift from a Hunter-Gatherer method to long fallow agriculture, the introduction of new tools is not necessary, which she cites as the reason the change was so easy. Part IV is concerned mainly with population density and how migration affected the timing and velocity of technological diffusion from Europe immediately succeeding the industrial revolution. These density levels range from one to ten representing virtually scarce areas to packed densities respectively. In this system, she notes that a gap exists between the lesser and the more populated countries. The United States is at level five, but technologically advanced, whereas some countries at level six and seven are far less technologically advanced. W.W. Rostow at the University of Texas at Austin assessed this in his critique of Boserup's work. As a reference, she notes that in 1975 the world's average population density was around thirty persons per square kilometer. (p. 10) Also from the historical point of view she notes that in 1500, China's 100-150 million people was already putting a strain on its resources. (p. 89) This data shows how with technological advancement over time, even if density increases, a country is not doomed to be a slave to its resources. One factor which she leaves out is that eventually, densely populated nations like The Netherlands opens up questions of political economy, as the Dutch do not actually subsist on their own resources. This "Netherlands Fallacy" appears to fly in the face of her technology recapitulates population argument as is critiqued by Phillip Bereano from the University of Washington in his critique of Boserup's theory. Joel Mokyr from Northwestern University cites one of the most frequently argued points of Boserup's thesis; that her states that somehow when population grows, it signals to start looking for and to adopt a more labor-intensive technology. "The problem is that she never explains that signal, nor how a society finds that new technology or how they search for it." (Mokyr, 1982) This problem is quite apparent in her discussion of third world countries that do not have the technology, but have certainly been burdened with the population increase associated with it. The author is careful not to repudiate or caution against the obvious recommendation in her theory. That implicit counsel is that s the poorest nations in the world, such as Haiti, Senegal, and Mauritania, should continue full steam ahead with their population growth until density and size spawn the needed pressure to force innovation upon them.