In his very practical approach to life, Swamiji teaches us how to preserve health and prevent disease by making the body a fit instrument for achieving the purpose of life. Swamiji, therefore, starts with the four primitive fountains of food, sleep, self-preservation, and sex, the body, and the breath, before delving deeper into the mind, emotions and personal relationships. He concludes the book by describing four paths of spiritual practice, any of which can be adopted, depending on one's temperament, to reach the goal of self-realization.