From mechanistic to functional behaviorism.

A shift from mechanistic behaviorism to functional behaviorism is presented against the background of two historical traditions, one with an emphasis on form, the other with an emphasis on function. Skinner's work, which made more contributions to a functional behaviorism than to a mechanistic behaviorism, exemplifies this shift. The two traditions and an account of Skinner's development of functional relations are presented in order to show Skinner's contributions to aligning modern behavior analysis with the functional tradition.