Man's mental functions have developed unevenly. Sometime during the la
st millennium the muscle man was superseded by the intelligent man. Th
e human psyche, besides intellectual capacity, includes a basic functi
on that can be called emotional capacity. This function can be studied
using the same approach as in the study of intellectual capacity. The
two functions are considered to be partly independent of each other.
Emotional capacity depends on the individual's genetic emotional make-
up (emotional genotype) and how this inherited set of qualities has be
en conditioned by environmental factors (emotional phenotype). Man's e
motional capacity is very little differentiated: emotionally, modern m
an still functions almost like Stone Age man. Intellectual capacity, h
owever, has undergone enormous development. As emotional capacity to a
large extent governs man's behaviour and intellectual capacity is the
instrument he uses to reach his goals, the uneven differentiation of
the mental functions may have consequences that are unfavourable to th
e survival of our species.