<P> As a result of the conjunction of a number of events in the early 20th century, behaviorism gradually emerged as the dominant school in American psychology . First among these was the increasing skepticism with which many viewed the concept of consciousness: although still considered to be the essential element separating psychology from physiology, its subjective nature and the unreliable introspective method it seemed to require, troubled many . William James' 1904 Journal of Philosophy...article "Does Consciousness Exist?", laid out the worries explicitly . </P> <P> Second was the gradual rise of a rigorous animal psychology . In addition to Edward Lee Thorndike's work with cats in puzzle boxes in 1898, the start of research in which rats learn to navigate mazes was begun by Willard Small (1900, 1901 in American Journal of Psychology). Robert M. Yerkes's 1905 Journal of Philosophy...article "Animal Psychology and the Criteria of the Psychic" raised the general question of when one is entitled to attribute consciousness to an organism . The following few years saw the emergence of John Broadus Watson (1878--1959) as a major player, publishing his dissertation on the relation between neurological development and learning in the white rat (1907, Psychological Review Monograph Supplement; Carr & Watson, 1908, J. Comparative Neurology & Psychology). Another important rat study was published by Henry H. Donaldson (1908, J. Comparative Neurology & Psychology). The year 1909 saw the first English - language account of Ivan Pavlov's studies of conditioning in dogs (Yerkes & Morgulis, 1909, Psychological Bulletin). </P> <P> A third factor was the rise of Watson to a position of significant power within the psychological community . In 1908, Watson was offered a junior position at Johns Hopkins by James Mark Baldwin . In addition to heading the Johns Hopkins department, Baldwin was the editor of the influential journals, Psychological Review and Psychological Bulletin . Only months after Watson's arrival, Baldwin was forced to resign his professorship due to scandal . Watson was suddenly made head of the department and editor of Baldwin's journals . He resolved to use these powerful tools to revolutionize psychology in the image of his own research . In 1913 he published in Psychological Review the article that is often called the "manifesto" of the behaviorist movement, "Psychology as the Behaviorist Views It ." There he argued that psychology "is a purely objective experimental branch of natural science", "introspection forms no essential part of its methods ..." and "The behaviorist...recognizes no dividing line between man and brute". The following year, 1914, his first textbook, Behavior went to press . Although behaviorism took some time to be accepted as a comprehensive approach (see Samelson, 1981), (in no small part because of the intervention of World War I), by the 1920s Watson's revolution was well underway . The central tenet of early behaviorism was that psychology should be a science of behavior, not of the mind, and rejected internal mental states such as beliefs, desires, or goals . Watson himself, however, was forced out of Johns Hopkins by scandal in 1920 . Although he continued to publish during the 1920s, he eventually moved on to a career in advertising (see Coon, 1994). </P> <P> Among the behaviorists who continued on, there were a number of disagreements about the best way to proceed . Neo-behaviorists such as Edward C. Tolman, Edwin Guthrie, Clark L. Hull, and B.F. Skinner debated issues such as (1) whether to reformulate the traditional psychological vocabulary in behavioral terms or discard it in favor of a wholly new scheme, (2) whether learning takes place all at once or gradually, (3) whether biological drives should be included in the new science in order to provide a "motivation" for behavior, and (4) to what degree any theoretical framework is required over and above the measured effects of reinforcement and punishment on learning . By the late 1950s, Skinner's formulation had become dominant, and it remains a part of the modern discipline under the rubric of Behavior Analysis . Its application (Applied Behavior Analysis) has become one of the most useful fields of psychology . </P>

What are the two disciplines that formed psychology