Nor is it advisable that I should speak of the founder of physiological medicine. His vast labours are the result of great genius, and have long influenced the medical world with all the weight of a master mind. Having been his pupil for many years, I shall never cease to admire his life of scientific labour. Nevertheless, I cannot refrain from remarking how much he has done to lessen the spirit of medical enquiry. By localizing all diseases, and by his system of irritation, without taking into account the constitution as a whole, how greatly is the labour of the physician reduced! how little knowledge is necessary on his part to be deemed worthy of the title of Doctor of Medicine! Once upon the highway of localization, once engaged in this contracted study, there is no stop. It is no longer necessary to be acquainted with all the organs, both in a state of health and of disease; the extent of territory to be explored is reduced. The fashion at the present day is, that a physician of this school should know only how to treat the diseases of one particular organ, and rarely of two; that he should be, in fact, a specialist. But are not the principal organs of the body, for the most part, mutually dependent on each other, and all of them subject to a general _consensus_? What is the consequence of this medical specialism? Why, that every physician so engaged thinks, and most conscientiously, that the patient before him labours under that particular disease to which he particularly devotes his attention. This is perfectly natural. The mind of man is so formed, that it is narrowed, and loses its powers of comparison and of judgment, whenever it is concentrated and brought to bear solely upon one subject, one single object. Man is no longer capable of reasoning upon a science or an art, when he puts it out of sight as a whole, in order to devote himself entirely to one of its parts; but ends by making the subject of his study the principal point, the all-important one, whence flow, in his opinion, all the rest; and finally assumes that a part is equal to the whole. When a patient complains of palpitation of the heart, he prescribes a bleeding, leeches, digitalis. If another complain of sense of weight or oppression, bleedings, softening syrups, troches, &c., are prescribed. If another complain of headache, dizziness, with threatening apoplexy, he is bled. Everything is treated locally, without inquiring whether the evil be or be not the effect of some general cause. Among a vast number of general causes, giving rise to disease, I purpose to treat of one, and that is excessive corpulence, termed obesity. In our recent medical works, no reference is made to this morbid predisposition, in regard to the diseases occasioned by it. I do not mean to say that superabundance of fat is the cause of all the ills that flesh is heir to; but I am persuaded and do affirm that it is often the primary cause of many diseases.