ABSTRACT
This chapter considers psychological approaches to war and militarism, and the nature of human motivation. The argument from animal behaviour is sometimes associated analogously with demographic factors. Evolution demanded that humans fought to survive. Our ancestors had an unending struggle against nature, in so far as this was possible, and consequently had to do battle against each other in the competition for limited resources. Einstein, who actually left Germany for Switzerland during the First World War to escape military service, like Freud, viewed the outbreak of war in 1914 with horror and despair. Strictly speaking, one should probably differentiate between massacre and genocide even though in everyday speech they tend to be used synonymously. If the massacres by Mithridates and Sulla were largely motivated by a desire for revenge, those committed by Claudius early in Rome's Imperial period can be safely attributed to fear, particularly fear of opposition.
