| Fruits of Philosophy ‑ Scholar, An Essay on the Principle, The Population Bomb, Principles of Political Economy, Enquiry Concerning Political J|Law of Population Wikipedia
Law of Population (1830) was a massive treatise written by Michael Thomas Sadler as a response to Thomas Robert Malthus's works on population growth, notably An Essay on the Principle of Population (first edition 1798). In his essay, Sadler refutes Malthus' conclusions regarding the geometric growth of populations and proposes that the growth of populations is a far less worrisome menace. At this period population growth had become a "political bugbear" throughout England, much in a way comparable to modern day fears of terrorism or Cold War fears of nuclear war.
In this work Sadler proposed many factors in models of population growth that are now widely accepted as fact, such as that "[Birth rates] tend to decline with increasing levels of prosperity."