Benjamin Franklin - Inventions and Scientific Inquiries - Population Studies

Population Studies

Franklin had a major influence on the emerging science of demography, or population studies. Thomas Malthus is famous for his rule of population growth and credited Franklin for discovering it. Kammen (1990) and Drake (2011) say Franklin's "Observations on the Increase of Mankind" (1755) stands alongside Ezra Stiles' "Discourse on Christian Union" (1760) as the leading works of eighteenth century Anglo-American demography; Drake credits Franklin's "wide readership and prophetic insight."

In the 1730s and 1740s, Franklin began taking notes on population growth, finding that the American population had the fastest growth rates on earth. Emphasizing that population growth depended on food supplies—a line of thought later developed by Thomas Malthus—Franklin emphasized the abundance of food and available farmland in America. He calculated that America's population was doubling every twenty years and would surpass that of England in a century. In 1751, he drafted "Observations concerning the Increase of Mankind, Peopling of Countries, &c." Four years later, it was anonymously printed in Boston, and it was quickly reproduced in Britain, where it influenced economists Adam Smith and later Thomas Malthus. Franklin's predictions alarmed British leaders who did not want to be surpassed by the colonies, so they became more willing to impose restrictions on the colonial economy.

Franklin was also a pioneer in the study of slave demography, as shown in his 1755 essay.