I have alluded already to the way in which the prevalent use of Machinery in practical life has affected our mental outlook on the world. It is curious that during this mechanical age of the last 100 years or so, we have not only come to regard Society in a mechanical light, as a concourse of separate individuals bound together by a mere cash-nexus, but have extended the same idea to the universe at large, which we look upon as a concourse of separate atoms, associated together by gravitation, or possibly by mere mutual impact. Yet it is certain that both these views are false, since the individuals who compose Society are _not_ separate from each other; and the theory that the universe, in its ultimate analysis, is composed of a vast number of discrete atoms is simply unthinkable. When we come to a practical and modern question like Medicine, the influence of the spirit in which it is approached on the course of the science is very easy to see. For if the science of Medicine is approached (as it perhaps mostly is to-day) in a spirit of combined Fear and Self-indulgence--fear for one's own personal safety, combined with a kind of anxiety to continue living in the indulgence of habits known to be unhealthy--if it is approached in this uncomfortable and contradictory state of mind, it is pretty obvious that its course will be similarly uncomfortable: that it will consist for the most part in a search for drugs which shall, without effort on our part, palliate the effects of our misconduct; in the discovery, as in a kind of nightmare, that the air round us is full of billions of microbes; in a terrified study of these messengers of disease, and in a frantic effort to ward them off by inoculations, vaccinations, vivisections, and so forth, without end. If, on the other hand, the science is approached from quite a different side--from that of the love of Health, and the desire to make life lovely, beautiful and clean; if the student is filled not only with this, but with a great belief in the essential _power_ of Man, and his command in creation, to control not only all these little microbes whose name is Legion, but through his mind all the processes of his body; then it is obvious enough that a whole series of different facts will arise before his eyes and become the subject of his study--facts of sanitation, of the laws of cleanly life, diet, clothing and so forth, methods of control, and the details and practice of the influence of the mental upon the physical part of man--facts quite equally real with the others, equally important, equally numerous perhaps and complex, but forming a totally different range of science.