Public bodies, Gentlemen, as well as individuals, have too often opposed the progress of science.... But, when have they been able to impede it?—Never. The iron grasp of tyranny and the intrigues of malice are alike innocuous to truth; the progress of science is irresistible and triumphant. On the present occasion, I feel it my duty to propose a new system, nor do I expect very different treatment; for though the gun of the soldier and the anathema of the priest be no longer connected, the malice of the interested and the intrigues of party occupy their place: the former were the measures of a barbarous; the last are those of a half-polished age. Fortunately, however, far from being formed to fear opposition—I court it. * * * * * The following sketch of a natural system of medical science is founded on the strict basis of physiology, and is, I trust, calculated to place, in a new and more interesting point of view, the beautiful relations which subsist between the sciences of anatomy and physiology and the art of medicine, as well as to lay the foundation of a more rational system of medical science. I do not, however, make this statement without a feeling of the utmost deference to the labours of the celebrated Cullen and Brown—the authors of the existing systems and of innumerable observations of the highest value in medical science. Nothing less than the firmest conviction of the truth and simplicity of the system I am about to propose, could have induced me to deliver it. First, however, I shall proceed to exhibit the present state of medical science. No system of the medical art can be just in its principles, and perfect in its application, which does not consider the derangement of the mechanical, vital, and intellectual functions _distinctly_, and trace each disease to the operation of its cause in the derangement of that particular function which was first produced, and which led to the derangement of all the rest. It has been the fate of all systems to be founded upon partial views of the functions. The system of the celebrated Cullen, for example, was founded merely upon the vital functions, and even upon a very limited portion of them—the state of the capillary vessels. Considering its extent, however, it was valuable.