人口論
The concept of the struggle for existence concerns the competition or battle for resources needed to live. It can refer to human society, or to organisms in nature. The concept is ancient, and the term "struggle for existence" was in use by the end of the 18th century. From the 17th century onwards the concept was associated with a population exceeding resources, an issue shown starkly in Thomas Robert Malthus’ "An Essay on the Principle of Population" which drew on Benjamin Franklin's "Observations Concerning the Increase of Mankind, Peopling of Countries, etc.".