This is a popular exposition of modern psycho-analytical theories of excessive aggression. After remarking that some degree of aggression is normal, emphasis is laid on the importance of unconscious aggression springing from early situations such as privation, jealousy of a younger child or of parents. The rest of the article is given to a discussion of the defensive aggression arising from anxiety and guilt under the four headings: (1) Destruction following despair. (2) Aggression as defence against retaliation. (3) Aggression as a provocation. (4) Aggression as a result of making another child the scapegoat.

Author's Abstract.