1. To the MEDICAL COLLEGE it will give a method of accurate diagnosis which will supersede the blundering methods now existing--a method of RAPIDLY enlarging and perfecting the materia medica--a method of exploring all difficult questions in Biology and Pathology, and a complete view of the constitution of man. 2. To the UNIVERSITY it offers a method of revising and correcting history and biography--of enlarging our knowledge of Natural History, Geology, and Astronomy, and exploring Ethnology. 3. To the CHURCH it offers a method of exploring the origins of all religions, the future life of man, and the relations of terrestrial and celestial life. 4. To the PHILANTHROPIST it offers the methods of investigating and supervising education and social organization which may abolish all existing evils. The foregoing were the initial steps and results in the development of Psychometry, simultaneously accompanied by those other discoveries in 1841, the scope and magnitude of which appear to me and to those who have studied my demonstrations, to be far more important than anything that has ever been discovered or done in Biological science, being nothing less than a complete scientific demonstration of the functions of the brain in all its psycho-physiological relations. To appreciate their transcendent importance, it is necessary only to know that the experiments have been carefully made, have often been repeated during the past forty-five years, and that all they demonstrate may also be demonstrated by other means, and fully established, if no such experiments could be made. The origin of this discovery was as follows. My advanced investigations of the brain, between 1835 and 1841, had added so much to the incomplete and inaccurate discoveries of Gall, and had brought cerebral science into so much closer and more accurate relation with cerebral anatomy and embryology, as illustrated by Tiedemann, that I became profoundly aware of the position in which I found myself, as an explorer, possessed of knowledge previously quite unknown, and yet, at the same time, however true, not strictly demonstrable, since none could fully realize its truth without following the same path and studying with the same concentrated devotion the comparative development of the brain in men and animals. Such zeal, success, and assiduity I did not believe could be expected. There might not be one man in a century to undertake such a task (for all the centuries of civilization had produced but one such man--the illustrious Gall), and when he appeared his voice would not be decisive. I would, therefore, appear not as presenting positive knowledge, but as contributing another theory, which the medical profession, regardless of my labors, would treat as a mere hypothesis.[1]