Psychology, the study of behaviour

William McDougall ( mək-DOO-gəl; 22 June 1871 – 28 November 1938) was an early 20th century psychologist who was a professor at University College London, University of Oxford, Harvard University and Duke University. He wrote a number of influential textbooks, and was important in the development of the theory of instinct and of social psychology in the English-speaking world. McDougall was an opponent of behaviourism and stands somewhat outside the mainstream of the development of Anglo-American psychological thought in the first half of the 20th century; but his work was known and respected among lay people.