No intelligent observer of the signs of the times can fail to notice among philosophical minds a marked reaction against the dominant scientific materialism of the past century, and a tendency to return to a more spiritual view of human nature and the world at large. Idealism, which has always had a strong hold upon the deepest thinkers of the world from Plato downward, is again coming into prominence, and many of the leading scientists of the day exhibit an inclination to adopt it as furnishing the most satisfactory explanation of the phenomena of nature. The present volume of the author is an attempt to construct a theoretical and practical system of phrenopathy, or mental-cure, on the basis of the idealistic philosophy of Berkeley, Fichte, Schelling, and Hegel. Its fundamental doctrine is that to think and to exist are one and the same, and that every disease is the translation into a bodily expression of a fixed idea of the mind and a morbid way of thinking. If by any therapeutic device you remove the morbid idea, which is the spiritual image after the likeness of which the body is formed, you cure the malady. The work lays no claim to originality except in the practical application of Idealism to the cure of the diseases of mind and body. It is the culmination of a. life-long study of human nature, and to which the previous volumes of the author may be viewed as introductory.