nature fits him for primitive not
civilized society; the complexity of the situation--response connection
and its necessary variation with minor elements in the external
situation and in the individual. Earlier writers, therefore, felt the
need of special theories of play. The best known of these theories are,
first, the Schiller-Spencer surplus energy theory; second, the Groos
preparation for life theory; third, the G. Stanley Hall atavistic
theory; fourth, the Appleton biological theory. Each of the theories has
some element of truth in it, for play is complex enough to include them
all, but each, save perhaps the last, falls short of an adequate
explanation.

Two facts growing out of the theory of play accepted by the last few
paragraphs need further discussion. First, the order of development in
play. The play activities must follow along the line of the developing
instincts and capacities. As the nerve tracts governing certain
responses become ready to act, these responses become the controlling
ones in play. So it is that for a time play is controlled largely by the
instinct of manipulation, at another time physical activity combined
with competition is most prominent, at another period imagination
controls, still later the puzzle-solving tendency comes to the point
followed by all the games involving an intellectual factor. This being
true, it is not surprising to find certain types of play characterizing
certain ages and to find that though the particular games may vary,
there is a strong resemblance between plays of children of the same age
all over the world. It must not be forgotten, however, that the
readiness of nerve tracts to function, and therefore the play responses,
depends on other factors as well as maturity. The readiness of other
tracts to function; past experience and habits; the stimulus provided by
the present situation; absence of competing stimuli; sex, health,
fatigue, tradition--all these and many more factors modify the order of
development of the play tendencies. Still, having these facts in mind,
it is possible to indicate roughly the type of play most prominent at
different ages.

Children from four to seven play primarily in terms of sensory
responses, imagination, imitation, and curiosity of the cruder sort.
Love of rhythm also is strong at this period. From seven to ten
individual competition or rivalry becomes very strong and influences
physical games, the collecting tendency, and