Population experts seemingly are puzzled by a strange phenomenon. As people get wealthier, they have smaller families.
This demographic transition turns logic upside down.
Of course, it is rational to assume that the richer a family, then they could afford/desire more children, but that is not what happens.
At one point forecasters believed that the increase in population would far outstrip food supply. With the surge in food production, that no longer was a factor in worries about population expansion.
Yet there is a mystery, no simple answer, why wealthy families tend now to have fewer children than those who are less well off.
In undeveloped nations people are inclined to have numerous offspring as so many do not survive because of health problems and inadequate food supply. Also, children can be useful workers to assist in farming.
In our world, illogical as it seems, the higher the income, the smaller the families.
At first glance, wealthy families are more aware of the opportunity costs of raising children, so that curtails their birth rates. Hence, they have smaller families.
Then too wealthy families probably are more conscious of trying to provide the best quality of life for their offspring, while maybe of secondary importance for poorer families as they cannot do much about this.
It should be perfectly obvious that reducing family size creates a socio-economic advantage; wealthy families probably consider that of paramount importance.
There is the psychological background to families where success is so crucial. Parents with a small number of children can dote on them, ensuring better education and spending more time with them.
Witness nowadays the fact that wealthy families are so keen to get their children in the best schools, even at the pre-kindergarten level.
Poor families may lack the other factors that make a good life; the other outlets that make for a good existence. An ancient psychology may persist.
Notwithstanding better hygiene and the increasing availability of medical care, the other considerations cited above appear to explain the reason for those who are well off to have a smaller number of children.