Introduction -- Evolution and war -- War and eugenics -- Morality in warfare -- Is war diminishing? -- War and the birth-rate -- War and democracy -- Feminism and masculinism -- The mental differences of men and women -- The white slave crusade -- The conquest of venereal disease -- The nationalisation of health -- Eugenics and genius -- The production of ability -- Marriage and divorce -- The meaning of the birth-rate -- Civilisation and the birth-rate -- Birth control.