that as they age many of them lose their hair, teeth, and hearing. We
cannot seem to agree that they become more or less anxious, loving, orwithdrawn. The field of aging and personality was intended to answersuch questions.
One possible explanation for the lack of common knowledge
about personality change in adulthood is that there areno changes.
But before we jump to that conclusion, we must bear in mind the par -
ticular problems that a common-sense focus has in formulating ideas
about aging. In order to detect a pattern, we need to see a phenome -
non repeatedly . Some parts of what we see are the result of chance,
some the result of an underlying regularity , and only repeated obser -
vations can tell which is which. The parents of a first baby are con -
cerned with every change, not knowing what is normal development
and what might be a sign of illness. By the third or fourth child, how -
ever, the pattern is familiar, and the experienced mother is something
of an expert in child development.
But we do not live long enough to have repeated experience with
adult development. We know our grandparents as old people, but we donot know what they were like as children. We can watch our parentsgrow old, but it is difficult to separate our own maturing perceptionsfrom real changes in them. We can, of course, observe our own life andthe lives of our friends, but we could expect to draw conclusions thenonly at the end of our lives. And we have grown up in a particular pe-riod of history whose twists and turns, rather than the aging process it-self, may have made us what we are.
In short, common sense does not provide the distance, or perspec -
tive, from which to grasp any facts about adult development except the
most obvious. Historical biographers, who can compare across the cen -
turies, and anthropologists (Myerhoff & Simic
′, 1978), who can contrast
cultures, can offer some insight. As psychologists, we base our approachon the premise that scientific measurement of personality characteris -
tics in aging people can also provide a basis for answering this question.
Quantitative investigations of large samples of people followed over aperiod of years can detect even very subtle changes with great objectiv -
ity . And psychologists have been concerned with issues of personality
development long enough that we now have data following the same in -
dividuals over the greater part of their lives. This book is based, first
and foremost, on the results of those studies. As we interpret them, theypoint clearly to the conclusion that personality forms part of the endur -8 PERSONALITY IN ADULTHOOD