That violence is widespread and possibly increasing in the 20th century, none will deny. Yet few scientists have investigated the subject. Wertham, a psychiatrist with much experience in examining and treating members of minority groups, delinquents, criminals, and others prone to suffer or commit violence, has written this book to explore the topic. He states that the most fruitful approach combines dynamic clinical psychiatry and sociology but adds, "It is often harder to obtain all the data of violence accurately than it is to interpret them. Description comes before analysis." Most of the book is a detailed description of 20th century violence, with some discussion of its causes.
As contributing factors, Wertham mentions alcohol, warlike toys, and advertising (including cigarette advertising). He expounds his objections to what he calls "the Malthus myth," but does not make clear why he thinks concern about overpopulation is either cause or result of violence.