Part One: Preamble: science and theory. Theories and learning. Part Two: Learning: stimulus-response explanations. Early behaviorism: Pavlov, Watson, Guthrie, and Thorndike. Skinner and operant conditioning. Hull and Spence: intervening variables. Traditional behaviorism re-examined. Hebb: a transition. Part Three: Learning: cognitive explanations. Tolman and Gestalt psychology. Bruner and categories. Piaget and cognitive development. Artificial intelligence. Part Four: Factors affecting learning. Memory and attention. Motivation. Social influences. Part Five: A last word. An integration and evaluation.