With physical birth the physical human body is exposed to the physical environment of the external world. Before birth it was surrounded by the protecting envelope of the mother’s body. What the forces and fluids of the enveloping mother-body have done for it hitherto, must from now onward be done for it by the forces and elements of the external physical world. Now before the change of teeth in the seventh year, the human body has a task to perform upon itself which is essentially different from the tasks of all the other periods of life. In this period the physical organs must mould themselves into definite shapes. Their whole structural nature must receive certain tendencies and directions. In the later periods also, growth takes place; but throughout the whole succeeding life, growth is based on the forms which were developed in this first life-period. If true forms were developed, true forms will grow; if misshapen forms were developed, misshapen forms will grow. We can never repair what we have neglected as educators in the first seven years. Just as Nature brings about the right environment for the physical human body before birth, so after birth the educator must provide for the right physical environment. It is the right physical environment alone, which works upon the child in such a way that the physical organs shape themselves aright.
Source: Rudolf Steiner – GA 34 – The Education of the Child in the Light of Anthroposophy
Translated by George and Mary Adams