684 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1914. 
The ability to satisfy needs, to perform onerous duties and to 
acquire culture demands the capacity for long-sustained volitional 
effort under the control of an idea of need or duty. This is work in 
its developed form. This capacity to work is not achieved suddenly. 
It is an acquired trait. The infant has no capacity to work; the 
capacity is acquired, in the normally developed individual, during 
the period between birth and maturity.'. It appears in late infancy 
and we exploit it in school by the sixth year. It develops very 
gradually up to the age of 7, more rapidly from 7 to 12, and increas- 
ingly fast during adolescence. 
The rise of the capacity for work is associated with and directly 
dependent upon a correlated and parallel development of (1) the 
power for volitional action in the plastic nervous system through the 
developmental stimulus of activity in play; (2) the development. of 
the capacity for volitional attention through the exercise of reflex 
attention in the instinctively controlled activities of play; (3) the 
development of the capacity for sustained enthusiastic effort through 
the exercise of the emotion of expectancy which holds attention in 
the emotion-suflused activities of play; and, finally, (4) the develop- 
ment of a moral sense of purpose or responsibility or ambition, which 
comes with a maturing of the social self. 
The growth of all these nervous and mental powers that make 
work possible begins in the simple and instinctive activities of the 
infant which every one recognizes as play. The young child can be 
educated in no other way. But later the development may be con- 
tinued either through play or work as above defined, and it is just 
here that the confusion arises concerning the relationships of play 
and work in education. To anticipate my conclusions, play, because 
of its emotional accompaniment, is a more efficient developer of all 
the fundamental powers used in work than work itself. 
The child’s activities develop progressively (1) in the muscular 
strength used; (2) in the variety, complexity, duration, and coordi- 
nation of movements; (3) in the number of instincts and desires and 
the form and intensity of their expression; (4) in the breadth of the 
associative processes used; and (5) in the span of sustained effort in 
the accomplishing of a desired end. 
Now, the activities exhibiting this progressive development may 
frequently be considered either play or work, according to the point 
of view. From the standpoint of the child there are only two classes 
of activity—internally impelled activity, or play, and externally 
impelled activity, or work. Any activity from the child’s standpoint, 
1 The roots of both play and work are present from the beginning. The struggle to satisfy physical 
needs or escape discomforts expressed by vocal, facial and general bodily movements may be called the 
roots of work. The struggle to satisfy sense, nervous, and mental needs, or the spontaneous actions and 
reactions of adjustment, may be called the roots of play. It is in these latter activities primarily that all 
the higher powers for work and play are developed. 
