Remember The Population Bomb? It was published in 1968 and was not only popular, but accepted as irrefutable truth by many thoughtful people during my college years, 1971-1975. The book's thesis was, as a Wikpedia article on the subject says, that there would be "mass starvation of humans in the 1970s and 1980s due to overpopulation, as well as other major societal upheavals." Because of this impending crisis, the book "advocated immediate action to limit population growth."