The subjects of erysipelas and pneumonia, and the man who had haemoptysis, were already suffering from depraved states of the blood, or of the organs to which it was determined; and from which, in the last two cases, it escaped in different quantities; while the patient who was attacked with pleurisy was surcharged with urea from defective action of his kidneys.

These several persons, therefore, were suffering, when they considered themselves in health - before the occurrence of the chill - from abnormal physiological states to which we can attribute the particular form of the disease which was set up, by the addition, in each case, of one and the same cause, viz., the chill. - But some escaped unhurt! Because in them the physiological state was sufficiently normal that a resisting and re-actionary power existed, which was competent speedily to restore the functions of the organs subjected to the shock of the chill, and to make them compensate for the temporary arrest by increased activity.

I have chosen this group of somewhat crude examples on purpose that their meaning may be the more perspicuous. They, most of them, exemplify states of health dependent on the fluids and excretory organs of the body. It would be easy to bring many examples of degraded health consequent on disease attributable to the nervous system.

I assume, then, that (in the course of these lectures) I have sufficiently demonstrated that the vestiges of disease stand first among the causes of death.

I have shown that so long as these vestiges exist they are causes of defect in the vital force, and thus act as factors of the essential and of the predisposing causes of fresh attacks of disease.

I have shown that the diseases, from which these vestiges result, are but the manifestations of pre-existent physiological states, to which, by some means, the last condition has been supplied, necessary to complete the conditions of existence proper to the disease, which then is developed in its characteristic features.

I have shown that these abnormal physiological states are indicated by the various conditions of impaired general health, "conditions not recognised as disease, but which certainly are not health."

The sum of it is this: -

1. The majority of diseases which we see excited by the various accidents of life are but the manifestations of pre-existent abnormal physiological states, which required only this last condition (the accident of life) to complete their development into the characteristic features of disease.

2. Those conditions "not recognised as disease, but which certainly are not health," are the faint expressions of these morbid physiological states, while still deficient in the condition necessary to complete their development into the recognised features of disease.

3. The multifarious and anomalous functional derangements which puzzle the physician, and make martyrs of the patients, depend, for the most part, upon the influence exerted by these morbid physiological states over the ordinary incidents of animal existence, which are thereby modified, coloured, and distorted.

4. During the whole of the time that the physiological conditions are disturbed, there is a greater or less defect in the vital force, and this defect, therefore, exists at a period anterior to what are usually understood as structural changes.

I have shown that these abnormal physiological states, recognisable under various forms of impaired health and attended by a legion of anomalous symptoms, may be traced back to still earlier periods in their history, when they require the greatest vigilance of the physician to detect any deviation from the standard of normal health.

Then I endeavoured to show in what direction we must look for the causes of these earliest and most occult deviations from the normal physiological state.

With this intention I pointed out that the "conditions of life" and the "vestiges of disease" have a direct influence on the vital force; that the alterations in it are transmissible to the germs of a succeeding generation; and that thus defects of force may be due to abnormal conditions of life in the individual, and to the vestiges, or vestiges of vestiges of disease in an ancestor. And I wish to draw your marked attention in this place to the fact, that it is to these defects transmitted from an ancestor, and to the conditions of life in the individual, that we must especially look for the causes of those first insidious deviations from health, which I have called "abnormal physiological states."

As I have shown that these incipient and insidious degradations of the vital force exist at a period anterior to such changes as are understood by the terms structural and organic, I think you will now understand why I said in my last Lecture that there could be no fact in Medicine of greater practical importance than this. My reason was - that the very dependence upon the conditions of life which exposes the force in the individual to degradation under unfavourable conditions, must render it amenable to elevation under the influence of conditions which are favourable. And thus we learn that there is a possibility of cure in states that would otherwise be beyond the reach of treatment.