Book excerpt: Seminar paper from the year 2014 in the subject Psychology - Social Psychology, grade: A, ( Atlantic International University ), course: PhD Project Management, language: English, abstract: The origins of aggression dominate psychological debate. Psychologists are divided on what really is the cause of aggression in human behavior. This has evoked the inconclusive nature v nurture debate on the origins of aggression. The psycho dynamic theory is a psychological theory Sigmund Freud (1856-1939) and his later followers applied to trace and explain the origins of aggression. Sigmund Freud’s psycho dynamic theory is founded on the assumption that human behavior is propelled by thoughts and feelings that lie in our sub conscious mind . Aggression refers to action or behavior intended to cause harm to a person toward whom it is directed . Thus aggression manifests itself in varied forms which can be verbal attacks, violent acts and threats to unleash destruction . However, the psycho dynamic theory has been criticized for over emphasis on innate personality at the exclusion of external effects in an individual’s environment which may predispose them to aggressive behavior. This paper analyses Sigmund Freud’s psycho dynamic theory in explaining the origins of aggression. The paper further argues that the psycho dynamic theory has its own inherent shortcomings when it comes to explaining the origins of aggression. A wholesome explanation of the origins of aggression can be achieved if theories such as the externally stimulated aggression and learned aggression theory are also considered as they offer complementary alternative aggression explanations.