Some notes on population history, the demographic transition and the demographic future of the world

A short summary of human population history, a critical analysis of available empirical evidence and an interpretation of data free of reverence toward the dominant theories bring to the conclusion that up to now the human population has experienced only two demographic regimes. The first was characterized by high rates of mortality and fertility. Its main characteristic was that man did not have the capability to control fertility and intervene on mortality so that periods of high demographic growth were followed by periods of pronounced demographic decline. In spite of this, at the end, the demographic history of men has been a success story. It is then argued that around 1850 an unprecedented demographic revolution was ignited by extraordinary advancements in medicine, chemistry and biology, as well as the development of new laboratory tools and techniques that opened the way to the introduction of powerful vaccines. This allowed defeating the most dangerous infectious diseases and waging a successful war against premature death. The final result was that the economically more advanced countries reached a new demographic regime, the modern regime, characterized by low fertility and low mortality rates. The fundamental characteristic of the modern regime is the capability of men to choose and determine his reproductive behavior and to control more and more the causes of death. According to present empirical evidence, the modern regime is not characterized by a demographic equilibrium, but by vastly spread situations of negative natural growth. Finally the paper argues that, in spite of the fact that deaths take place in the natural and chronological order, the modern regime is not necessarily more efficient than the natural regime. The main reason is that in this new demographic situation economic growth brings to demographic disequilibrium and the different historical moments in which the demographic “transition” has started in different countries is creating the preconditions for migration flows of unprecedented size. A paragraph of the paper is also devoted to a revisit and formalization of Carlo Cipolla hypothesis on energy and demographic growth and to the analysis of its validity both in the past and today.