As individual diseases are not arranged under the table, I may, in order to render my meaning perfectly obvious, give one or two examples of this mode of classification. Thus with regard to the classes or first and most general divisions of disease, _fracture_ is a disease of the mechanical functions, _syphilis_ of the vital functions, and _mania_ of the intellectual functions. With regard to the orders or second and less general divisions of disease in the last of these classes, _amaurosis_ is a disease of impression or sensation, _mania_ of mental operation, and _paralysis_ of expression or volition. And with regard to the genera or subdivisions of disease in the second of these orders, _fatuitas_ is a disease of diminished mental operation, _mania_ of depraved mental operation, and _vigilia_ of increased mental operation. Farther, with regard to the combination of disease under the last class, (sleep itself consisting in the quiescence of almost all the intellectual functions), _dreaming_ consists chiefly in the quiescence of sensation, _somnambulism_ chiefly in that of mental operation and _incubus_ chiefly in that of volition. With regard to the articles of the materia medica, or rather with regard either to external or internal applications, the correctness of my arrangement, as indicating their influence upon the different classes of organs, will, on the slightest consideration, appear equally evident; pressure, for instance, affects the mechanical, mercury the vital and opium the intellectual system. But, like the diseases which they remedy, it will appear, that each of these also affects all of the functions, though in a less direct manner than that which I have just now particularly pointed out as its object, and upon which the exact place of each in a systematic arrangement ought to depend. It cannot, therefore, be a just objection to this arrangement, that it throws each of what are commonly called diseases under these different classes, as, in reality, each of the common diseases is more properly three, and exists under three natural classes. Even in this way, does every physician, though unaware of it, consider them, and therefore, instead of giving any new complexity to nosology, it merely explains and simplifies that complexity which ever has existed in the nature of disease. In other words, it is natural, and developes and simplifies only the combinations of nature.