nurse must leave him to himself, at first only for a moment or two,
re-entering the room in a matter-of-fact way without speaking to him,
and again leaving it. Soon he will learn that a temporary separation
does not mean that we have abandoned him for all time. Then the period
of absence can be gradually lengthened till all difficulty disappears.
Once his attention is removed from the grown-up people who mean so
much to him, his natural impulse to explore and experiment with his
playthings will show itself. Those toys are best which are neither
elaborate nor expensive. For a little child a small box containing a
miscellaneous collection of wooden or metal objects, none of them
small enough to be in danger of being swallowed, forms the material
for which his soul craves. Everything else in the room may be out of
his reach. A dozen times he will empty the box and then replace each
object in turn. He will arrange them in every possible combination,
and then sweep the whole away to start afresh.

At eighteen months of age observation and imitative capacity will
have made more complex pursuits possible. As a rule the objects which
are most prized and which have most educative value are those which
lend themselves best to the actions with which alone the child is
familiar. Hence the supreme importance of the doll and the doll's
perambulator. The doll will be treated exactly as the child is treated
by the nurse. It will be washed, and dressed, and weighed, and put to
bed in faithful reproduction of what the child has daily experienced.
Dusting, and sweeping, and laying the table will be exactly copied. If
a child has no opportunity of being familiar with horses, if he has
not seen them fed, and watered, and groomed, and harnessed, he may not
find any great satisfaction in a toy horse, or pay much attention to
it, no matter how costly or realistic it may be.