 Benjamin Disraeli included the phrase "a density of population implies a severe struggle for existence" in his novel "Sybil" (1845), which was about the plight of the working class in Britain.In "An Essay on the Principle of Population", Thomas Robert Malthus argues that a population will increase exponentially if unchecked, while resources will only increase arithmetically.This is seen graphically in the adjacent image and is commonly referred to as the Malthusian curve.