CHAPTER 4
The Search for Growth
or Decline in Personality
If we want to know whether personality changes across the adult years,
the most straightforward way of proceeding would seem to be to mea-sure personality in young and old people and see if there are any notice-able differences. This simple prescription turns out to be more complexthan one might at first imagine. There are several excellent discussionsof measuring change and disentangling aging, birth cohort, and time-of-measurement effects (e.g., Kausler, 1982; Schaie, 1977), complete withdiagrams and statistical formulas. Our purpose here is not to teachmethodology but to show why a question as apparently straightforwardas “Does personality change with age?” is not straightforward at all andto review evidence on whether personality grows or declines with age.
Growth and decline are the most obvious and fundamental of de -
velopmental processes. Children grow taller each year until they reach
adult stature; thereafter they remain at about the same height for manyyears, until in old age the settling of bones in the vertebral columnmakes them shrink somewhat. Many biological functions, notably sexu -
ality , show similar curves, as do some, though by no means all, of the
intellectual functions, such as short-term memory and spatial visualiza -
tion abilities.
Many physical, biological, and social functions, however, do not
exhibit the pattern of growth and decline. Some characteristics, likegender or eye color, are established by birth and show no significantchange across the lifespan. Variables of another class go through a pe -
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