The previous three chapters have been concerned with theoretical positions relating fairly narrowly to subdivisions of the lifespan. In the present chapter we are concerned with issues which transcend these boundaries: Issues of overall explanatory frameworks and of general developmental processes. Assumptions concerning such factors have to a considerable extent determined the definition of the boundaries themselves. It should also be noted that the criteria! ages themselves have a history: That is to say, certain ages have been taken by many authors as transition points, independently of extensive theorisation or empirical research. The ages of 7 years and 14 years have an especially long history. For example, classical divisions of the lifespan noted by James Sully in his Teacher’s handbook of psychology include those of Beneke (0–3; 3–7; 7–14); Pfisterer (0–2; 2–7; 7–14); and Crichton Browne (0–1; 1–7; 7–14). Each also proposed a final pre-adult division, defined by age only in the last version as 14–21. The number 7 has been described as a “magical” number in psychology in several senses, and its role in theoretical subdivisions of childhood certainly has a ritual quality. The age of 7 years is of course a critical one in such theories as Piaget’s. 1