August 14, 1998


Women of the working class, especially wage workers, should not have more than two children at most. The average working man can support no more and the average working woman can take care of no more in a decent fashion.

Margaret Sanger(1883-1966)

In 1968, biologist Paul Ralph Ehrlich, then age 36, published a book called The Population Bomb. Much as Thomas Malthus did in in 1798, Ehrlich reasoned that if population growth continued as it was, that the Earth would be decimated by more people than it could feed. Ehrlich proposed various ways that population growth could be checked in order to prevent a complete disaster.

The important condition of both Ehrlich's and Malthus' argument was: if the population continued to grow as it now does...

Now, a scant 30 years later, not only has the population not continued to grow, but it is shrinking. Not only do we now have zero population growth in the industrial nations, but growth is now measured in minus numbers.In other words, the number of births per woman has dropped to less than 2 offspring per female. (Males are irrelevant since they don't have children. There are enough sperm in single ejaculation to populate the next generation of the world. In other words, men and their sperm cells are cheap; women and their egg cells are precious.) Since slightly less than half of the number of births is female, it takes an average birth rate of more than 2 children per female to keep the population steady. It has to be more than 2 because some females die before they reach maturity and some will have no children. In countries where the infants death rate is high, it has to be much more than 2. In the third world, a woman, on average, has to have many more than two children to just keep the population stable.

In the United States, the average number of children born per woman is about 2.1, which is slightly below what is needed to keep the population stable. The population of the United States is increasing, but this is mostly due to immigration.

Between 1990 and 1995, the birth rate in Sweden fell from 2.12 to 1.6. By March of this year, it fell to 1.42, which is the same birth rate as Japan. In those countries, we can expect the population to shrink. This is because more people die than are born. While people, on average, are living longer, everyone still dies. This is unlikely to change --ever.

It is becoming more and more common in the developed world for women to work outside the home. Not only does this not allow time for rearing a large family, it reduces the desire for one. Ready availability of birth control allows a woman to plan the size of her family. Even in Italy, a staunch Roman Catholic country, the number of children per woman has dropped by about half of what it was. This means that a large number of women are either using various birth control methods or abstaining.

When I was a child, there were very few professional women. Women who worked were usually unmarried. Once married, they settled down to the serious business of having and raising children. Most considered their role as supporting their husbands. The few women who also had careers usually abandoned them while they were rearing small children. They went back to work only after their children were in school. True career women rarely had more than one or two children. Now this practice has become fairly common. The number of women entering the professions is approaching that of men. Among non-professional women, most women now have jobs outside the home.

An example of how quickly population dynamics can change can be found in Sweden. 1990 was a birth-boom year. They now have 130,000 eight year olds in school. Three years from now, the number of 8 year olds will be just half of what it is now. Those people who have to plan for classrooms, teachers etc. really have to hustle to keep up with the changes.

In the past, birth rates would fall off when times were bad and pick up when times were good. On the farms, every child was an extra pair of hands. Now much of farming is mechanized. Just as birth rates fell when farm people moved to the city, they aren't anywhere near what they used to be on the farm.

Now times are good and the birth rate is falling. This is not what anyone would have predicted based on past behavior.

So what are my predictions for the future? I wouldn't dare try to predict. While birth rates are dropping now, having more than two children might become popular again in a few years. It is not possible to make accurate predictions about what people will do as far as having children is concerned, in much the same way as it is not possible to make long-term economic predictions with any degree of accuracy. I guess the world will just have to wing it, as it always has.

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