That which the physiology of the sense-organs aims at is to make functioning--with what one might call suggestive violence--follow as a logical necessity from the anatomical and physiological details. The delicate intricacies of the retina, of the cortical organ, of the papillæ of smell and taste, have been laid bare with such a completeness that it seems to need but one more breath, the last and lightest of all, to wake in this wondrous instrument the melody of life. But it is just this last lightest breath that remains lacking, and is not to be secured by any mere dexterity in method however highly developed. Set to where one will, whether at the first turning over of the ovum, whether upon the heights of the evolution of sense, everywhere the miracle stands before us complete. It is entirely owing to the vast numbers and continuous relays of workers in the realm of science that the conviction that upon this path, a description becoming ever more minute and exact, there is nothing real to be achieved has not already gained much more ground than is the case. As oft as pen and scalpel fall from a trembling hand, into the breach leaps youthful vigour, and begins the battle anew with fresh courage. The like holds good of the latest branch of psychology, the working out of prerequisite conditions of function. On all hands a similar scene meets the eye. Each new result, each fresh-won eminence avails nothing but to open out in yet more impressive fashion the vista of endless, towering mountains beyond. Here it would almost seem as if men intentionally slurred over the patent fact that the explanation of consciousness, of the power to think, already in every case presupposes this itself, and that every sensation, if at all present as such, already possesses also a certain content of consciousness. It is the chase after the horizon,--the attempt by a vigorous and decided advance to see over on the other side of one’s own limit of vision,--perpetual progression without progress!