Radical behaviorism
Radical behaviorism is a philosophy developed by B. F. Skinner that underlies the experimental analysis of behavior approach to psychology. The term 'radical behaviorism' applies to a particular school that emerged during the reign of behaviorism. However, radical behaviorism bears little resemblance to other schools of behaviorism, differing in the acceptance of mediating structures, the role of private events and emotions, and other areas.
Radical behaviorism has attracted attention since its inception. First, it proposes that all organismic action is determined and not free. However, there are deterministic elements in much of psychology. Second, it is considered to be 'anti-theoretical', although this is a fundamental misunderstanding of the role of theory in a radically inductive scientific position, which rejects hypothetico-deductive methods and theory construction about things in unobservable, unmeasurable "other places" (such as the mind).

# Natural science
Radical behaviorism inherits from behaviorism the position that the science of behavior is 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, a denial that 'ghostly' causation is a relevant factor in behavior, and a penchant for operationalizing. Its principal differences are an emphasis on operant conditioning, use of idiosyncratic terminology, a tendency to apply notions of reinforcement to philosophy and daily life to a thoroughgoing degree, and, particularly, a distinctly positive position on private experience.
Importantly, radical behaviorism embraces the genetic and biological endowment and ultimately evolved nature of the organism, while simply asserting that behavior is a distinct field of study with its own value. From this two neglected points issue: radical behaviorism  is thoroughly compatible with biological and evolutionary approaches to psychology - in fact, as a proper part of biology - and radical behaviorism does not involve the claim that organisms are 'tabula rasa,' without genetic or physiological endowment.
Skinner's psychological work focused on operant conditioning, with emphasis on the schedule of reinforcement as independent variable, and the rate of responding as dependent variable. Operant techniques are a venerable part of the toolbox of the psychobiologist, and many neurobiological theories - particularly regarding drug addiction - have made extensive use of reinforcement. Operant methodology and terminology has been used in much research on animal perception and concept formation - with the same topics, such as stimulus generalization, bearing importantly on operant conditioning. Skinner's emphasis on outcomes and response rates naturally lends itself to topics typically left to economics, as in behavioral economics. The field of operant conditioning can also be seen to interact with work on decision making, and had influence on AI and cognitive science.

# The basics: operant psychology
Skinner saw that classical conditioning didn't 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 has two basic purposes (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/pleasant or negative/aversive.
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. R+
- If the probability of a behavior is increased as a consequence of the withdrawal of a stimulus, that stimulus is a negative reinforcer R-
- If the probability of a behavior is decreased as a consequence of the presentation of a stimulus, that stimulus is a positive punisher. P+
- If the probability of a behavior is decreased as a consequence of the withdrawal of a stimulus, that stimulus is a negative punisher or response cost punishment. P-
Negative reinforcement and punishment are often confused. It is important to note that a reinforcer is anything that increases the likelihood that a behavior will happen again. A punisher will always decrease behavior.
B.F. Skinner loathed the use of punishers and he argued their undesirable side effects were often worse than the actual behavior that was to be reduced.
Instrumental conditioning is another term for operant conditioning that is most closely associated with scientists who studied learning that occurred over discrete trials, such as runs 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 tells something about the future of the organism: That in the future, the reinforced behavior will be likely to occur more often.

# Common misunderstandings
Many textbooks wrongly 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. Such claims ignore Skinner's research into operant conditioning which emphasizes the importance of consequences in modifying discriminative responses.
Many textbooks argue that radical behaviorism maintains the position that animals (including humans) are passive receivers of conditioning, failing to take into account 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.
Noam Chomsky's Review of Verbal Behavior contains the error that Skinner is an S-R psychologist
Radical Behaviorism has often been confused with logical positivism. Skinner was not a logical positivist and recognized the importance of thought as behavior. This position is made quite clear in About Behaviorism.
For a current review and summary of his book Verbal Behavior see the article Verbal Behavior

# Explaining behavior and the importance of the environment
John B. Watson argued against the use of references to 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 subject matters. (The challenge was that objective observation and measurement was often impossible.) 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, and are just more behavior to explain. Explaining behavior by referring to thought or feelings are pseudo-explanations because they 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
- One can manipulate behavior by manipulating the environment
This holds only for explaining the class of behaviors known as operant behaviors. This class of behavior Skinner held as the most interesting study matter.
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 does not consider people a blank slate, or tabula rasa
Many textbooks seem to 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 in the organism. However, the black box is not private events, but physiology. Skinner considers physiology as useful, interesting, valid, etc., but not necessary.

# 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. Unlike John B. Watson's behaviorism, private events are not dismissed as "epiphenomenon", 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. This is Watson's position, not Skinner's.

# Outgrowths
There are radical behaviorist schools of animal training, management, clinical practice, and education. Skinner's political views have left their mark in small ways as principles adopted by a small handful of utopian communities such as Los Horcones, 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.
Skinner's theories on Verbal Behavior have seen widespread application in therapies for autistic children that are based on Applied Behavior Analysis (ABA).

# Notes
-  Mecca Chiesa: Radical Behaviorism: The Philosophy & The Science
-  Skinner, B.F. Are Theories of Learning Necessary? 1950 
-  Huitt and Hummel (1997)
-   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. 142-143
-  MacCorquodale, K. (1970). On Chomsky's review of Skinner's Verbal Behavior. Journal of the Experimental Analysis of Behavior, 13, 83-99. 
-  Skinner, B. F. (1974). About Behaviorism. New York: Knopf.
-  Skinner, B.F. "On Having A Poem" in which he states:"I am not an S-R psychologist." also in About Behaviorism where he states this position again.