William McDougall was a British psychologist born in 1871, known for his work in the field of psychology and his contributions to the understanding of human behavior. He is particularly recognized for his theories on instinct and emotion, which he detailed in his influential book, An Introduction to Social Psychology. McDougall believed that instincts drive human actions and that emotions play a crucial role in social interactions. In addition to his work in psychology, McDougall was also involved in the study of social psychology and psychological theory. He served as a professor at various institutions, including University College London and Harvard University. His ideas laid the groundwork for future research in psychology, influencing both academic thought and practical applications in understanding human behavior.