It is right that mothers should appreciate the important part which
the environment plays in all the mental processes of children, and in
their physical condition as well; that they should understand that
good temper and happiness mean a proper environment, and that constant
crying and fretfulness, broken sleep, refusal of food, vomiting, undue
thinness, and extreme timidity often indicate that something in this
direction is at fault.

Nevertheless, we must be careful not to overstate our case. We must
remember how great is the diversity of temperament in children--a
diversity which is produced purely by hereditary factors. The task of
all mothers is by no means of equal difficulty. There are children in
whom quite gross faults in training produce but little permanent
damage; there are others of so sensitive a nervous organisation that
their environment requires the most delicate adjustment, and when
matters have gone wrong, it may be very difficult to restore health of
mind and body. When a peculiarly nervous temperament is inherited,
wisdom in the management of the child is essential, and may sometimes
achieve the happiest results. Heredity is so powerful a factor in the
development of the nervous organisation of the child that, realising
its importance, we should be sparing in our criticism of the results
which the mothers who consult us achieve in the training of their
children. A sensitive, nervous organisation is often the mark of
intellectual possibilities above the average, and the children who are
cast outside the ordinary mould, who are the most wayward, the most
intractable, who react to trifling faults of management with the most
striking symptoms of disturbance, are often those with the greatest
potentialities for achievement and for good. It is natural for the
mother of placid, contented, and perhaps rather unenterprising