We have said that disease was an obstruction or diminution of vital energy, caused by a violation of the laws of nature. The effects of this obstruction are various, depending on the organ obstructed or disenabled, the extent of that obstruction, and the vital power existing in the system to overcome the offending causes. The different symptoms by which the different forms of disease are characterized, are arranged by medical authors into classes or kinds, giving to each class a different name, as fever, which is subdivided into ten or twelve kinds or colors, as scarlet, yellow, etc.; consumption, fits, dropsy, rheumatism, etc. These are not separate and distinct diseases, but a manifestation or effect of disease.

Fever is not a disease. but the effect of an effort of nature to overcome disease. Let an individual be exposed to the cold after sweating, without any exercise, and what is the result ? Pain in the head and back, cold chills succeeded by a preternatural degree of heat, pulse strong and quick. What is the cause of these symptoms ? A contraction of the minute blood-vessels of the surface and the pores of the skin, in consequence of which the circulation is thrown upon the large blood-vessels, occasioning fullness and pain in the head, back, etc., and retention of morbific agents, occasioning an increased action of the heart and arteries. This increased action generates more heat than in a healthy state, which is retained in consequence of the pores of the skin being closed, through which medium the extra heat escapes in a healthy state. This retained heat gives a name to the disease, as fever means heat. It must appear evident that this retained heat, called fever, is not the disease, but the effect of disease. Disease assumes the most dangerous forms when there is a deficiency of fever, as in low typhus fever, cholera, cold plague, paralysis, etc. Fever is an evidence that nature is active; whereas a loss of fever, before the cause is removed, would be a certain indication of approaching death.

The effect of disease, then, is to produce all those different phenomena that physicians have classed under different names, as so many different diseases.