Radical behaviorism was pioneered by B. F. Skinner and is his "philosophy of the science of behavior." It refers to the philosophy behind behavior analysis, and is to be distinguished from methodological behaviorism—which has an intense emphasis on observable behaviors—by its inclusion of thinking, feeling, and other private events in the analysis of human and animal psychology. The research in behavior analysis is called the experimental analysis of behavior and the application of this field is called applied behavior analysis (ABA), which was originally termed "behavior modification."
Radical behaviorism as natural science
Radical behaviorism inherits from behaviorism the position that the science of behavior is a natural science, a belief that animal behavior can be studied profitably and compared with human behavior, a strong emphasis on the environment as cause of behavior, and an emphasis on the operations involved in the modification of behavior. Radical behaviorism does not claim that organisms are tabula rasa whose behavior is unaffected by biological or genetic endowment. Rather, it asserts that experiential factors play a major role in determining the behavior of many complex organisms, and that the study of these matters is a major field of research in its own right- that of Darwinism. 
The most precise way to describe radical behaviorism as "radical" is to understand that instances such as evolution and cell division are occurrences that just happen. There is no third party that assists in this transformation; they can, however, be explained by other naturally occurring events. They should not try to be explained through objects that are not tangible, e.g., ghosts or inner entities. Radical behaviorists therefore conclude that naturally occurring events may be examined in relation to our past and present environments through the effect they have on human beings.
The basics: operant psychology
Skinner saw that classical conditioning did not account for the behavior most of us are interested in, such as riding a bike or writing a book. His observations led him to propose a theory about how these and similar behaviors, called operants, come about.
Roughly speaking, in operant conditioning, an operant is actively emitted and produces changes in the world (i.e., produces consequences) that alter the likelihood that the behavior will occur again.
As represented in the table below, operant conditioning involves two basic actions (increasing or decreasing the probability that a specific behavior will occur in the future), which are accomplished by adding or removing one of two basic types of stimuli, positive reinforcers or negative reinforcers.
|Stimulus type||Effect: increase behavior||Effect: decrease behavior|
|Positive Reinforcer||Add positive reinforcer||Remove positive reinforcer|
|Punishment||Remove punishment||Add punishment stimulus|
In other words:
- If the probability of a behavior is increased as a consequence of the presentation of a stimulus, that stimulus is a positive reinforcer.
- If the probability of a behavior is increased as a consequence of the withdrawal of a stimulus, that stimulus is a punishment.
- If the probability of a behavior is decreased as a consequence of the presentation of a stimulus, that stimulus is a punishment.
- If the probability of a behavior is decreased as a consequence of the withdrawal of a stimulus, that stimulus is a positive reinforcer.
Instrumental conditioning is another term for operant conditioning that is most closely associated with scientists who studied running through a maze. Skinner pioneered the free operant technique, where organisms could respond at any time during a protracted experimental session. Thus Skinner's dependent variable was usually the frequency or rate of responding, not the errors that were made or the speed of traversal of a maze.
Operant conditioning affects the future of the organism, that is how the organism will respond after the actions summarized above occur.
Explaining behavior and the importance of the environment
This section possibly contains original research. (December 2020)
John B. Watson argued against speaking of mental states and held that psychology should study behavior directly, holding private events as impossible to study scientifically. Skinner rejected this position, conceding the importance of thinking, feelings and "inner behavior" in his analysis. Skinner did not hold to truth by agreement, as Watson did, so he was not limited by observation.
In Watson's days (and in Skinner's early days), it was held that psychology was at a disadvantage as a science because behavioral explanations should take physiology into account. Very little was known about physiology at the time. Skinner argued that behavioral explanations of psychological phenomena are "just as true" as physiological explanations. In arguing this, he took a non-reductionistic approach to psychology. Skinner, however, redefined behavior to include "everything that an organism does," including thinking, feeling and speaking, and argued that these phenomena were valid scientific subject matters. (The challenge was that thoughts and feelings cannot be observed objectively.) The term radical behaviorism refers to just this: that everything an organism does is a behavior.
However, Skinner ruled out thinking and feeling as valid explanations of behavior. The reasoning is this:
Thinking and feeling are not epiphenomena nor have they any other special status; they are just more behavior to explain. Explaining behavior by referring to thought or feelings would be pseudo-explanation, because thoughts and feelings merely point to more behavior to be explained. Skinner proposed environmental factors as proper causes of behavior because:
- Environmental factors are at a different logical level than behavior and actions.
- One can manipulate behavior by manipulating the environment.
This holds only for explaining operant behaviors. Skinner held operant behaviors to be the most interesting class of behaviors.
Many textbooks, in noting the emphasis Skinner places on the environment, argue that Skinner held that the organism is a blank slate or a tabula rasa. Skinner wrote extensively on the limits and possibilities nature places on conditioning. Conditioning is implemented in the body as a physiological process and is subject to the current state, learning history, and history of the species. Skinner did not consider people a blank slate, or tabula rasa.
Many textbooks confuse Skinner's rejection of physiology with Watson's rejection of private events. It is true to some extent that Skinner's psychology considers humans a black box, since Skinner maintains that behavior can be explained without taking into account what goes on inside the organism. However, the black box is not private events, but physiology. Skinner considers physiology useful, interesting, valid, etc., but not necessary for operant behavioral theory and research.
Private events in a radical behaviorist account
Radical behaviorism differs from other forms of behaviorism in that it treats everything we do as behavior, including private events (such as thinking and feeling). Indeed, this is one reason why Skinner's philosophy is considered radical. Unlike John B. Watson's behaviorism, private events are not dismissed as "epiphenomena," but are seen as subject to the same principles of learning and modification as have been discovered to exist for overt behavior. Although private events are not publicly observable behaviors, radical behaviorism accepts that we are each observers of our own private behavior.
Many textbooks, in emphasizing that Skinner held behavior to be the proper subject matter of psychology, fail to clarify Skinner's position and implicitly or even explicitly posit that Skinner ruled out the study of private events as unscientific. Skinner explicitly noted that private events were essential for behaviorists to understand and account for, though he also considered them beyond the limits of direct analysis. 
There are radical behaviorist schools of animal training, management, clinical practice, and education. Skinner's philosophical views have left their mark in principles adopted by a small handful of utopian communities, such as Los Horcones and Twin Oaks, and in ongoing challenges to aversive techniques in control of human and animal behavior.
Radical behaviorism has generated numerous descendants. Examples of these include molar approaches associated with Richard Herrnstein and William Baum, Howard Rachlin's teleological behaviorism, William Timberlake's behavior systems approach, and John Staddon's theoretical behaviorism. Contextual behavioral science, associated with the works of Steven C. Hayes, is also an interpretation of radical behaviorism.
This section needs additional citations for verification. (December 2020)
Many textbooks and theorists like Noam Chomsky label Skinnerian or radical behaviorism as S–R (stimulus–response, or to use Skinner's term, "respondent"), or Pavlovian psychology, and argue that this limits the approach. Chomsky has further argued Skinner's experimental results could not be extended to humans. Contemporary psychology rejects many of Skinner's conclusions, although some[who?] scholars find his work into operant conditioning, which emphasizes the importance of consequences in modifying discriminative responses, useful when combined with current understandings about the uniqueness of evolved human thought compared to other animals.
Many textbooks[by whom?] argue that radical behaviorism maintains the incorrect position that animals (including humans) are passive receivers of conditioning, although others[who?] have countered that:
- operant behavior is titled operant because it operates on the environment
- operant behavior is emitted, not elicited: Animals act on the environment and the environment acts back on them, or
- the consequence of a behavior can itself be a stimulus; one needs not present anything for shaping to take place.
Radical behaviorism is sometimes negatively described[by whom?] as a form of logical positivism,[further explanation needed] a doctrine that had come into disfavor by the late 20th century. Skinnerians maintain that Skinner was not a logical positivist and recognized the importance of thinking as behavior, as Skinner emphasizes in About Behaviorism.
- Schneider, Susan M., and Morris, Edward K. (1987). "A History of the Term Radical Behaviorism: From Watson to Skinner". The Behavior Analyst, 10(1), p. 36.
- Chiesa, Mecca (1974). Radical Behaviorism: The Philosophy and the Science. Reprinted by Authors Cooperative (1994): Boston, Massachusetts. ISBN 0962331147, ISBN 978-0962331145.
- Staats, Finley, Minke, Wolf, 1964, "Reinforcement variables and the control of reading responses"
- Staats and Butterfield, 1965, "Treatment of non-reading in a culturally-deprived juvenile delinquent: an application of reinforcement principles"
- Krasner and Ullmann, 1965, "Research in behavior modification"
- Bryan O. Midgley; Edward K. Morris. "NATURE AND NURTURE IN SKINNER'S BEHAVIORISM". Mexican Journal of Behavior Analysis. 24 – via UNAM.
- James M. Johnston; H. S. Pennypacker; Gina Green (2019). Strategies and Tactics of Behavioral Research and Practice. Routledge. ISBN 9781138641594.
- Baum, William. "What is radical behaviorism? A review of Jay Moore's Conceptual foundations of radical behaviorism ..." Radical Behaviorism 95.1 (2011): 119-126. ProQuest. Web. 12 Jan. 2011.
- Huitt, W. & Hummel, J. (1997). "An Introduction to Operant (Instrumental) Conditioning". Valdosta, Georgia: Valdosta State University.
- Skinner, B.F. "On Having A Poem" in which he states: "I am not an S–R psychologist." He states this position again in About Behaviorism.
- Malone, John C., and Cruchon, Natalie M. "Radical Behaviorism and the Rest of Psychology: A Review/Précis of Skinner's "About Behaviorism"". Behavior and Philosophy. 29.1 (2001): 31-57. Jstor. Web. 12 Jan. 2011.
- Skinner, B.F. "The operational analysis of psychological terms". APA. Retrieved August 11, 2020.
- Chomsky, N. (1959) "A Review of B.F. Skinner's Verbal Behavior". In Leon A. Jakobovits and Murray S. Miron (eds.), Readings in the Psychology of Language, Prentice-Hall, 1967, pp. 142–3.
- MacCorquodale, K. (1970). "On Chomsky's review of Skinner's Verbal Behavior". Journal of the Experimental Analysis of Behavior, 13, 83–99.
- Chomsky, Noam (December 27, 1971). "The Case Against B.F. Skinner". New York Review of Books.
- Arthur W. Staats (2012). The Marvelous Learning Animal. Retrieved April 18, 2018.
- Skinner, B.F. (1974). About Behaviorism. New York: Knopf.
- Wyatt, W. Joseph (2001). "Some Myths about Behaviorism That Are Undone in B.F. Skinner's 'The Design of Cultures'". Behavior and Social Issues, (11)1, pp. 28–30.
- Gaynor, Scott T. (2004). "Skepticism of caricatures: B.F. Skinner turns 100". The Skeptical Inquirer, 28(1), pp. 26–29.
- Holland, J.G.; Skinner, B.F. (1961). Analysis of behavior. McGraw-Hill.