Heinz Werner's orthogenetic principle
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Heinz Werner's orthogenetic principle is a foundation for current theories of developmental psychologySameroff, A. J. (2010). A unified theory of development: A dialectic integration of nature and nurture. Child Development, 81, 6-22. and developmental psychopathology.Cicchetti, D., & Cohen, D.J. (1995). Perspectives on developmental psychology. In D. Cicchetti, and D.J. Cohen (Eds.), Developmental Psychopathology, Vol. 1: Theory and Methods (Pp. 3-20). New York: Wiley.Sroufe, L.A., Egeland, B., Carlson, E.A., & Collins, W.A. (2005). The Development of the Person. New York: Guilford Press. Initially proposed in 1940,Werner, H. (1940). Comparative psychology of mental development. NY: International Universities Press, Inc. it was formulated in 1957{{cite book|last=Lerner|first=Richard M.|title=Concepts and Theories of Human Development|url=https://books.google.com/books?id=K9bon0TH_S0C&pg=PT267|year=2013|publisher=Psychology Press|isbn=9781135681883|page=267}}Werner, H. (1957). The concept of development from a comparative and organismic point of view. In D. B. Harris (Ed.), The concept of development. Minneapolis: University of Minnesota Press, p. 126. and states that "wherever development occurs it proceeds from a state of relative globality and lack of differentiation to a state of increasing differentiation, articulation, and hierarchic integration." It is an example of an organismic theory based on the intrinsic activity of living systems and is parallel to Piaget's genetic epistemology both emphasizing a holistic view of development.
In contrast to stage theories of development such as Sigmund Freud's description of psychosexual development that posited a particular sequence of behavior, Werner's principle provides a direction for development that can be applied to any behavioral domain.Baldwin, A. L. (1957). Theories of Child Development. New York: Wiley. He asserted that the principle provided a single framework for understanding change in child psychology, psychopathology, ethnopsychology, and individual differences. He believed that although the content of these areas may be different, there was a formal similarity of the sequences within each domain moving from the global to the hierarchically integrated.