This book contains Julius A. Dresser's summary of mental science and the ability to heal the sick with mental and spiritual power. As the son of Horatio Dresser - an acquaintance and adherent of Phineas Quimby, the founder of the New Thought movement - Julius felt obliged to carry on his father's legacy by explaining the beliefs he held. Citing both ancient philosophy and religion, Julius begins by saying knowledge of mental healing is neither new nor novel: rather, it has practiced through history. Referring repeatedly to Christianity and Jesus Christ as an example of mental healing in action, Dresser aims to illustrate how P. P. Quimby rediscovered it. His experiences with tuberculosis, where conventional medicine in the form of camomile did more harm than good, are detailed. Quimby would later go on to assert that exciting, uplifting experiences such as riding a horse did far more for his tuberculosis than any other method.

Allan Kardec's supreme handbook about the world of the spirits and the movement of Spiritism is a valuable and insightful guide to existences beyond our corporeal realm. Kardec begins this work by delving into the historical significance of spirits, their connection with God and the physical universe. How spirits are situated in the world, and how they move unseen between the planes of existence, is discussed. The second part concentrates on The Spirit World in greater detail. The types of spirits and how they are incarnated are detailed, with Kardec proposing that several distinct planes of existence are extant, and that most individuals proceed through life without knowing or seeing their influence. A chapter is devoted to how spirits might intervene in our everyday, corporeal world. Often these excursions have a purpose; the spirits are on a mission to inform someone, or change something, that harmony may be restored.