PRELIMINARY LECTURE TO THE COURSE OF ANATOMY AND PHYSIOLOGY; EXHIBITING THE OUTLINE OF A NATURAL SYSTEM OF THESE SCIENCES. GENTLEMEN, The functions of man are the most interesting objects of Science. Physics and Morals are equally involved by them. It is in them that the physical sciences terminate, and that the moral sciences have their origin. Of what avail are the former, but to develope the influence of external bodies upon the functions of man? What are the latter, but the results of the reaction of that influence upon men in society? To explain them is the business of physiology; and if it have hitherto failed in doing so—if it have even neglected the noblest of all the functions—I should say the noblest branch of philosophy—the intellectual functions of man, and have abandoned them to persons totally incapable of developing them, because totally ignorant of the structure on which they depend, and who have left them in a state of greater obscurity than that in which they found them, that is the fault of physiologists, and not of their science. In these lectures, I shall at least be influenced by the deepest sense of such errors. But it is not merely the philosophy of the human mind, or rather of the intellectual functions of man, that have thus been abandoned to barbarism. The science itself has never been systematized; and all its individual parts have been so neglected, that the other sciences and the arts dependent upon it, have been left in similar obscurity. I shall endeavour to shew that it is by the aid of physiology alone that, in explaining the functions of the eye, for instance, we can render perfect the theories of colour and of vision; that, in explaining the functions of the ear, we can construct rational ones of phonics and of hearing; that in explaining the functions of the organ of voice, we can illustrate the formation of letters, and the origin of languages; that, in explaining the functions of the muscles, we can establish those first principles of taste in the fine arts, the very existence of which have so often been questioned, and so deliver a theory of movement and of attitude, applicable to sculpture, the higher species of painting, gesture in oratory, &c. In fine, it is by physiological means only, that we can construct a natural theory of medicine, and render precise and easy, the most delicate and the most difficult of the operations of surgery. To effect these purposes, nothing is more necessary than arrangement, because it at once involves facts and their theory, or the reasonings founded upon them. * * * * * In considering a natural arrangement of Anatomy and Physiology, it appears to me an unquestionable point, that it ought to indicate, at a single glance, the relation of all the functions to and their dependence upon each other.