Happiness over the Life CourseThe Causes of Adult Outcomes
Equations (1) to (3) give us a good idea of the effect of in-
tervening at different stages in a person’s life. But it is also
important to understand what is going on inside the black
box. How, for example, are all the different adult outcomes
determined? Even if you do not think happiness is a valu-
able outcome, you may want to know how to affect adult
income, education, employment, crime, family life, and
health. Figure 1.4 shows how these adult outcomes are
affected by the outcomes of childhood: it represents equa-
tion (4).
There is a very clear pattern. Intellectual development is
the most powerful predictor of income, qualifications, and
employment. Behavioral development is the best predictor
of prosocial living and attachment to a partner. And emo-
tional development is much the best predictor of mental
and physical health. This is important because mental health
is the strongest proximate influence on life- satisfaction, and
therefore the aspect of childhood that best predicts adult
mental health (i.e., childhood emotional health) is also a
good predictor of adult life- satisfaction.
The Causes of Child Outcomes
Finally we can examine what determines the child out-
comes themselves (equation 5). This is crucial. Childhood
is not a dress rehearsal. It is life itself— to be lived to the full.
So what produces a happy, emotionally healthy child?
In Figures 1.5 (a) and (b) we look at how each of the
child outcomes at 16 depends on the experience of family