Malthus' father was a personal friend of the philosopher and skeptic David Hume and a disciple of Jean-Jacques Rousseau. At first an Anglican pasteur, Thomas Malthus published his Essay on the Principle of Population in 1798. It enjoyed a great success and he became an economist. He also wrote Principles of Political Economy.
His doctrine is founded on the idea that population grows exponentially (or geometrically) and thus faster than the arithmetic growth of resources. In consequence humanity is headed toward famine. He distinguished two kinds of ways of returning to equilibrium -- destructive ways (war and famine) and voluntary ways (decreasing the birth rate).
Malthus was essentially an empiricist and based his writings on the harsh realities of his times unlike, for example, William Godwin whose widely read Political Justice took for granted the perfectibility of mankind and foresaw a millennium in which rational men would live prosperously and harmoniusly without laws and institutions.
His ideas influenced the work of Charles Darwin on natural selection and provoked a lively debate that continues to this day.
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