Ours is a world of amazing multiplicity. It is a world of endless changes, increasing divergences and ever widening differentiations. So broad and boundless is the multiplicity around us and in us that it has been aptly described as a "perpetually multiplying multiplicity." Back of all of this boundless multiplicity is an ultimate unity. The unity and continuity of phenomena have become the corner stones of science. The various sciences approach perfection as they approach the unity of first principles. No system of thought or practice which fails to recognize these principles can ever become a science. The order and continuity exhibited throughout nature's processes demonstrate her underlying unity and lawfulness.

To the ignorant and superstitious Nature exhibits a mighty chaos of events and a dread display of power. Nature is never contemplated with a clear conception of its adaptation to the purposes or ends of Cosmic Order. To the scientist and philosopher the more we learn of creation the more conspicuously does uniformity of design appear to pervade its every department. The essential unity of phenomena is a cornerstone of modern science. Biological phenomena is no less a unit. Newer conceptions in biology emphasize the oneness of the body; the close interlacement and interdependence of structure and function in an integrated organism; rather than, as formerly, the structure and function of its theoretical parts.

An organism is a functional unit. Organs may be local and circumscribed, functions reach throughout the whole body. If we define an organ by the distance its products reach, rather than by its surface, an organism ceases to be heterogenous. Organs are made up of their inner media as much as of their histological elements and the inner medium of an organ reaches far beyond its anatomical border. Physiologically an organ is much greater than it is anatomically. By means of its secretion, each gland extends over the whole body. So do the lungs and the digestive system. The structural and functional integrity of every part of the body is essential to the functional and structural integrity of the whole body.

In illness the body preserves the same unity as in health. Not only is it true that no disturbance remains strictly confined to a single organ, that the body is a sick whole, but, it is also true that the whole body contributes to healing and recovery. The old anatomical conception of organism which looked upon the body as an assemblage of more or less independent parts, led physicians to consider "each disease" as a specialty.

The schools of physic have invented and classified numerous diseases; over twenty thousand. In 1930, a National Conference on Nomenclature of Disease, met in Manhattan to consider a numerical system of designating the many diseases, for doctors find it difficult to remember and keep straight, so many names, and the different names for the same diseases, as for instance, Pott's disease, vertebral caries, and tuberculosis of the spine--three names for the same condition.

The various drugless schools have accepted the nosological classifications of the schools of physic and are, today, in common with the drug and knife schools of medicine, treating and curing diseases. The Hygienic System, on the other hand early decided as Trall expresses it (Hydropathic Encyclopedia, Vol. 1, p. 33; Vol. 2, p, 72), that "nosologies are all unphilosophical and absurd."

Others also have regarded disease as a unit. Samuel Thompson, founder of Physio-Medicalism, and his followers thought, in the words of Prof. Curtis, of that school, that "Disease is one, . . . The symptoms are one, . . . and the treatment must be one . . ." Physio-Medicalists defined disease as "the inability of an organ to perform its proper functions, and in this sense it is a unit." Dr. Samuel Henry Dickson, of Britain, developed a system which he called the Chrono-Thermal-System based on the principles of (1) "the periodicity of movement of every organ and atom of all living tissues," (2) "the intermittency and unity of all diseases, however named and however produced," and (3) "the unity of action of cause and cure; both of which involve change of temperature." Priessnitz and his followers disregarded, to a great extent, all systems of nosological arrangement. Dr. J. H. Rausse, of the Water Cure School says: "Before I attempt to define the terms health and disease, I must point out that there are really no species and varieties differently marked off one from another; that the individuals of every species and variety have dissimilarities among themselves; that the transitions from one species to the other are so imperceptible, that with certain individuals and concrete cases it cannot be determined with certainty to which species they belong. This is particularly the case with the different diseases, and even the line of demarcation between health and disease is in cases of reality very wavering, in a word, the denominations of species, etc., are not borrowed from reality, and from here delivered over to human ingenuity, but vice versa, have originated in the human mind, and from there have been transferred to reality, because the former cannot operate without them." (The Water Cure, 1845, p. 18). In 1890 Louis Kuhne, of Germany, published his The New Science of Healing, in which he developed the principle that "there is only one cause of disease and there is only one disease, which shows itself under different forms."

Florence Nightingale, who taught the English physicians and surgeons the value of cleanliness, declares in her Notes on Nursing (1860), pp. 32-3: "Is it not living in a continual mistake to look upon disease, as we do now, as separate entities, which must exist, like cats and dogs? Instead of looking upon them as conditions, like a dirty and a clean condition, and just as much, under our own control; or rather as the reactions of kindly nature, against the conditions in which we have placed ourselves.

"I was brought up, both by scientific men and ignorant women, distinctly to believe that small-pox, for instance, was a thing of which there was once a first specimen in the world, which went on propagating itself, in a perpetual chain of descent, just as much as that there was a first dog, (or a first pair of dogs) and that small-pox would not begin itself any more than a new dog would begin without there having been a parent dog.

"Since then I have seen with my eyes and smelt with my nose smallpox growing up in first specimens, either in close rooms, or in overcrowded wards, where it could not by any possibility have been 'caught' but must have begun.

"Nay, more, I have seen diseases begin, grow up and pass into one another. Now, dogs do not pass into cats.

"I have seen, for instance, with a little overcrowding, continued fever grow up; and with a little more, typhoid fever; and with a little more, typhus, and all in the same ward or hut.

"Would it not be far better, truer, and more practical, if we looked upon disease in this light?

"For diseases, as all experience shows, are adjectives, not noun substantives."