A systematic knowledge of the powers and limitations of the human mind and soul before maturity and the characteristic changes which they undergo at puberty will throw a flood of light on the boy-problem. Juvenile psychology may be divided into child psychology, covering the period from birth to puberty, and adolescent psychology, covering the period from puberty to maturity. Boyhood is the interval between birth and physical maturity, the latter being reached at the age of twenty-four or twenty-five, when the bones, muscles, and organs of the body have attained their complete development. Legal maturity, or majority, comes at the end of the twenty-first year, when the disabilities of infancy are removed and the boy is presumed by law to have acquired sufficient intelligence, judgment, and moral discernment to take his place in the community as a citizen, and is then vested with all the rights, duties, and obligations of an adult, even though mental maturity (reckoned at the time the brain cells cease to grow and judgment and reason have fully ripened) is deferred until he is approximately fifty years of age. We may roughly divide the boy’s life into four periods of psychic unfolding in accordance with the table on page 32. +----------------+-------------+-------------------------------------+ | PERIOD | AGE | CHARACTERISTICS | +----------------+-------------+-------------------------------------+ | | | Imaginative faculty is | | IMAGINATIVE | Birth to 8 | dominant; acquisition of | | | Infancy | locomotion, speech and elementary | | | | knowledge; birth | | | | of moral concepts. | +----------------+-------------+-------------------------------------+ | | | Individualism; selfish | |INDIVIDUALISTIC | 8 to 12 | propensities; want of regard | | | Early | for rights of others; imitative | | | Boyhood | faculty is ascendant. | +----------------+-------------+-------------------------------------+ | | | Hero-worship; gang affiliations; | | HEROIC | 12 to 16 | puberty and early | | | Early | adolescence; fundamental | | | Adolescence | organic changes; sex-consciousness; | | | | age of experimentation; | | | | character-building period; psychic | | | | disturbances; exceptional | | | | plasticity of mind; high | | | | degree of emotionalism; | | | | susceptibility to religious |