The history of the child's attention is the history of the development of the organization of his behavior. This history begins at the moment of birth. Initial attention occurs through hereditary nerve mechanisms that organize the reflex processes according to the principle of the dominant that is familiar in physiology. This principle establishes that in the operation of the nervous system, the organizing point is a dominant focus of excitation that inhibits the process of other reflexes and is augmented at their expense. The dominant nerve process is the organic base of the process of behavior that we call attention.