B. F. Skinner

Skinner developed the theoretical philosophy that became radical behaviorism. This concept rejects internal observations known as mentalistic events (Olson & Hergenhahn, 2009). Skinner rejected terms such as drive, motivation, and purpose as aspects of behavior because they reflected personal mental experiences which he believed were unscientific and did not uphold the fundamental tenets of the science of psychology. He believed only the observable and measurable aspects of behavior were the only important aspects of psychological science. Although he built on the work of Watson and Pavlov, his work was considered revolutionary by his peers.

Equally, or possibly more important was Skinner's design of the operant conditioning chamber and his innovations in operant conditioning. He developed respondent and operant behaviors as well as two types of conditioning - Type S or respondent conditioning (classical conditioning) which stresses the significance of a stimulus causing a desired response and Type R (R for response) or operant conditioning which stresses response.

Skinner's theories, especially that of conditioning, continues to have a profound effect on psychology. Without knowing, many individuals use Skinnerian theory daily. Mothers all over the world give their children "time-outs" - a commonly used concept based on Skinner's theory. His theories on behavior modification are applied to contemporary problems such as phobias, eating disorders, and other problematic behaviors such as gambling. Skinner's influence covered childrearing, advertising, management, education, and self-help to a far greater extent than any of this twentieth century peers. His theories have withstood one of the greatest assays…the test of time.

Olson, M. H., & Hergenhahn, B. R. (2009). An introduction to theories of learning (8th ed.). Upper Saddle River, NJ: Pearson/Prentice Hall.