Question: Who wrote an essay on the principle of population?
Answer: Thomas Robert Malthus
Disambiguated questions and answers: question: Who was originally known to have written an essay on the principle of population?
Who was later identified as to having written an essay on the principle of population?
answer: anonymous
Thomas Robert Malthus
Natural Questions answer: Thomas Robert Malthus (from the Wikipedia article "An Essay on the Principle of Population")