Final answer:
John B. Watson identified as a behaviorist, a proponent of a psychological field focusing on observable behavior rather than internal mental processes.
Step-by-step explanation:
John B. Watson considered himself to be a behaviorist. This field of psychology emphasizes the study of observable behaviors over internal mental processes. Watson was a staunch advocate for behaviorism and significantly influenced its development as a central psychological theory. He believed that psychology should be an objective science without focus on unobservable mental states. Behaviorism gained prominence in the early 20th century with Watson as one of its key figures, along with later contributions from B.F. Skinner, who also focused on behavior but added the concept of operant conditioning, explaining how choices are influenced by rewards and punishments.