originally created by Pepper (1972). Both of them asserted that multiple lenses should be used to observe behaviors and also agreed that genetic factors would interact with environmental factors. Nature and nurture should not be separated since the two dimensions should cooperate together to impact human behaviors and development. Based on the current literature review and argument, this writer believes that Pepper’s four world hypotheses provide a better conceptual framework for combining different dimension approaches together in order to have a better understanding on how people gain knowledge.
Continuity and Discontinuity
One of major classic themes in developmental psychology is the debate over developmental continuity or discontinuity (Nakagaki, 2011). This issue has been debated over and over again for decades in developmental psychology. Some scholars assume that development should be divided into several stages to represent the developmental curves. Adolph, Berger, & Leo (2011) examined the developmental continuity of the locomotion stages, from crawling toward walking. This study found developmental milestones which have several stages with similar structural and movement characteristics. The other famous discontinuity example is Piaget’s Cognitive Developmental Stage theory which includes the sensorimotor,