B.F. Skinner's theory of language development is no different from his general theory of behaviorism. It is a simple theory based, like all of Skinner's work, around a structure of rewards and punishments, each reinforcing certain types of behaviour as good or bad. People begin to repeat actions that lead to pleasure and avoid actions that lead to pain. This is called "conditioning," which is the same thing as creating a habit.
Skinner's theory of behaviorism is central to his view of language. Human beings define right and wrong relative to their conditioned experienced of pleasure and pain, respectively. A certain action, if it receives a painful response, will be avoided, while those with a pleasurable response, or a reward, will be considered good. Human behaviour is totally conditioned by this pleasure/pain nexus. Behaviour, then, is the creation of habits—a habit is developed with an action, done repeatedly, that receives a reward of some kind. Language is no different.
Children begin to speak “nonsense” words, or babble. None of these are provided with any reward. As soon as the child begins to mimic the language of his parents, the interest of the parent is piqued. The result is that children, when they speak a recognisable word, are rewarded by their parents. As a result, those words and phrases are remembered and the nonsense words (that get no attention) are forgotten.
Skinner's theory is extremely simple and easy to apply. This is its main benefit. People do respond to rewards, especially over time, and become habituated to those actions that have lead to praise. This simplicity makes performing research and understanding behaviour very easy. Humans are merely animals responding to external stimuli only.
Skinner has had his share of critics. Problems with Skinner's theory of language development are substantial. Skinner does not take into consideration the complexity of grammar, which cannot be explained through mere imitation of parents. Even more, children often have a hard time imitating the complex sounds of their parents in the first place. Writers like N. Chomsky hold that biological necessity is a better explanation for language development. Chomsky's view, to put it simply, is that human beings need language to cooperate and therefore survive. Therefore, the human mind is already wired to receive language.
Skinner's theory reduces human beings to mere machines, or at best, bundles of nerve endings responding to external rewards and punishments. Most of the criticism of Skinner, and Chomsky included, have considered his approach exceptionally simplistic and unable to explain the complex reasons and ideas of humans.