We watch the decline of symptoms and the "return" of health and the subsequent development of a different group of symptoms and lose the continuity of the etiological thread because the "two-diseases" are so unalike.

It is now fully recognized that insanity introduces no new principle of action in to the processes of mind; that the laws of mind remain always the same. A change of condition produces a change of result so that "theoretically, it would be possible to take a series of men with a most 'normal' man at one end and a most pronouncedly insane one at the other, and to arrange those intervening in such a way as to show, through insensible gradations, the transition from one extreme to the other. To determine, in a series, the individual in whom abnormality first appears would be impossible.

"Such a gradual transition from normality to extreme insanity may, at times, be roughly traced in a single individual, as in the disease known as 'paralytic dementia.' Here, a man, usually in the prime of life, passes by imperceptible stages into a condition of profound dementia."

The principle of continuity and unity is here fully recognized, as is also the unity of "normal" and the "abnormal," as far as it applies to mental "diseases." ! It now needs only to be recognized that good health and poor health are both health; and that disordered liver function, for instance, introduces no new principles of action into the processes of the liver. Theoretically, it would be possible to take a large series of men, with a most normal man at one end and a pronouncedly diabetic man at the other, "and arrange those intervening in such a way as to show, through insensible gradations, the transition from one extreme to the other. To determine, in such a series, the individual in whom abnormality first appears would be impossible."

The law of continuity does not negate the possibility of the sudden appearance of new forms or new conditions. It only negatives the possibility of any such sudden appearances which have been unprepared. Nothing can come into existence without a long, even if it be a secret, history. Every leap, however wide, and every "new disease," however different, and however sudden its appearance, is always preceded by a chain of predetermining causes. When a new stage or step appears, which appears to be a new "disease," it has been gradually prepared below the surface of events. Pathology tends to widen in extent and grow in complexity, as its causes continue to pile up and operate. In each "type of disease," as in the aggregate of "types", the multiplication of effects has continually aided the transition from a more homogeneous to a more heterogeneous state. In a succession of "diseases", from a "lower" (simple) to a "higher" (complex) type, and a consentaneous greater degree of complication, many factors cooperate in effecting the pathological evolution. There are -varieties, but not species in pathology.

The more I study the manner of the evolution of pathology, the more am I impressed with its unity, even in full view of its multiplicity of forms and manifoldness of stages. All the "diseases" of the nosology are but an aggregate of evolutional results; which, while they appear to the superficial observer as specific and independent entities, are parts of one unified whole. Pathology in many parts of the body does not represent many kinds of pathology, nor many different kinds of evolution, nor yet, many diversified causes, but one evolution going on everywhere after the same manner. "Diseases" do not exist sui generis.

There is a fundamental oneness of pathology beneath great diversity of form. Specific forms of "disease" involve the law of diversity and differentiation manifested throughout nature in an infinite variety of transitions. The so-called, specific disease, the symptom-complex, counts for little in pathology. It is only the temporary expression of a "type"; it is a shadow, a reflection, image, but is not the reality back of the symptom. It is a transient, passing shadow, a ripple on the stream of life, which flows on regardless. Nature does not work by producing water-tight compartments, with secret drawers absolutely shut off, isolated and insulated from all the rest. On the contrary, there is invariably a direct, or else subtle, secret and absolute interdependence of one on all and all on one.

There is an equally constant struggle against, with a slow-yielding to, the antecedents of pathology. Back of this degeneration are various causes against which the body puts up a continuous, but losing struggle. At times the forces of life offer a more violent resistance to these causes of decay and this struggle makes itself felt as pain, fever, inflammation, swelling, rapid pulse, rapid respiration, diarrhea, skin eruptions, etc. These and the symptoms which accompany them are vital emergency measures instituted for the purpose of destroying and eliminating the causes of the degeneration and to repair tissue damages as far as this may be possible. As life advances, from infancy to middle-age, as the sphere of life widens and the individual conies in contact with an increasing number and variety of pathoferic influences, one tissue after another and one organ after another breaks down before the onslaught of impairing influences. A Greek label is attached to each break and the individual has a "new disease", or a "complication" of the "old one." Not only are names given to local expressions, but as they undergo developmental changes, new names are attached to them.

Parts not only evolve as the whole evolves, but the whole evolves as the parts evolve. Just as the body, as a whole, grows larger at the same time that the heart or the liver develop, so, the general regressive metamorphosis of the body grows greater as the degenerative changes in any of its organs grow greater.

So with the many so-called pathologies seen in a rapidly deteriorating, or in a dead, organism--these local states are not independent of each other, nor are they unconnected with preceding pathological states. Pathology never comes butt-end first.

The process is continuous and unbroken and all of its various steps or stages constitute a unit. As the cumulative effects of persistent, perhaps increasing, causes manifest themselves, we behold the breakdown of one tissue after another. Each break receives a separate name or number, is endowed with a quasi-individuality and becomes the object of special treatment.

When the organs of the body begin to break down and falter in their function, it is easy and natural for the wreck of one organ to be followed soon by the wreck of another, due to failing support from the faltering organ. All of the organs have been crippled more or less by the common causes of organic impairment, and many of them are already on the verge of a breakdown. Every successive development adds some impetus to the general deterioration of the body. If the pancreas is the first to collapse, the patient is said to have diabetes; then; as one organ after another follows the pancreas to the scrap-heap, the resulting "diseases" are regarded as complications of diabetes. This is just as correct as to look upon "diabetes" as a complication of some one of the many pathological developments that precede or accompany it. Malnutrition resulting from crippled digestive organs: crippled carbohydrate metabolism, in diabetes: impaired kidney excretion, in Bright's disease; lessened circulation, in heart affection; insufficient oxidation in pulmonary tuberculosis; impeded cell-renewal in arteriosclerosis, are only some of the examples of failing support resulting from the crippling of important organs, which hasten the break-down of other organs and build "complications." An additive resultant emerges out of the new concatenation.