4. Success and Failure. The outline of stages as given earlier is properly applicable to a revitalization movement which is completely successful. Many movements are abortive; their progress is arrested at some intermediate point. This raises a taxonomic question: how many stages should the movement achieve in order to qualify for inclusion in the category? Logically, as long as the original conception is a doctrine of revitalization by culture change, there should be no requisite number of stages. Practically, we have selected only movements which passed the first three stages (conception, communication, and organization) and entered the fourth (adaptation). This means that the bulk of our information on success and failure will deal with circumstances of relatively late adaptation, rather than with such matters as initial blockage of communication and interference with organization.