Feist−Feist: Theories of
Personality, Seventh
EditionII. Psychodynamic
Theories- Erikson: Post−Freudian
Theory
(^254) © The McGraw−Hill
Companies, 2009
form. Rather, it develops, or should develop, according to a predetermined rate and
in a fixed sequence. If the eyes, liver, or other organs do not develop during that crit-
ical period for their development, then they will never attain proper maturity.
In similar fashion, the ego follows the path of epigenetic development, with
each stage developing at its proper time. One stage emerges from and is built upon
a previous stage, but it does not replace that earlier stage. This epigenetic develop-
ment is analogous to the physical development of children, who crawl before they
walk, walk before they run, and run before they jump. When children are still crawl-
ing, they are developing the potential to walk, run, and jump; and after they are ma-
ture enough to jump, they still retain their ability to run, walk, and crawl. Erikson
(1968) described the epigenetic principle by saying that “anything that grows has a
ground plan, and that out of this ground plan the parts arise, each part having its
time of special ascendancy, until all parts have arisen to form a functioning whole”
(p. 92). More succinctly, “Epigenesis means that one characteristic develops on top
of another in space and time” (Evans, 1967, pp. 21–22).
The epigenetic principle is illustrated in Figure 9.1, which depicts the first
three Eriksonian stages. The sequence of stages (1, 2, 3) and the development of their
component parts (A, B, C) are shown in the heavily lined boxes along the diagonal.
Figure 9.1 shows that each part exists before its critical time (at least as biological
potential), emerges at its proper time, and finally, continues to develop during sub-
sequent stages. For example, component part B of Stage 2 (early childhood) exists
during Stage 1 (infancy) as shown in Box 1B. Part B reaches its full ascendance dur-
ing Stage 2 (Box 2B), but continues into Stage 3 (Box 3B). Similarly, all components
248 Part II Psychodynamic Theories
Children crawl before they walk, walk before they run, and run before they jump.