.. every step of the upward way is strewn with wreckage of body, mind, and morals.

Adolescence is a new birth, for the higher and more completely human traits are now born.

Civilization is so hard on the body that some have called it a disease, despite the arts that keep puny bodies alive to a greater average age, and our greater protection from contagious and germ diseases.

Modern man was not meant to do his best work before forty but is by nature, and is becoming more so, an afternoon and evening worker.

The years from about eight to twelve constitute a unique period of human life.

Constant muscular activity was natural for the child, and, therefore, the immense effort of the drillmaster teachers to make children sit still was harmful and useless.

There is no more wild, free, vigorous growth of the forest, but everything is in pots or rows like a rococo garden... The pupil is in the age of spontaneous variation which at no period of life is so great. He does not want a standardized, overpeptonized mental diet. It palls on his appetite.