Adolescence as the time when an individual ‘recapitulates’ the savage stage of the race’s past.

Muscles are in a most intimate and peculiar sense the organs of the will.

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.

Abundance and vigor of automatic movements are desirable, and even a considerable degree of restlessness is a good sign in young children.

The teens are emotionally unstable and pathic. It is a natural impulse to experience hot and perfervid psychic states, and it is characterized by emotionalism. We see here the instability and fluctuations now so characteristic. The emotions develop by contrast and reaction into the opposite.

Precisely what menstruation is, is not yet very well known.

Puberty for a girl is like floating down a broadening river into an open sea.