But if we would correct all the damage done instead of merely preventing further damage or building up internal resistance against a still active destructive process; if we would so eliminate the effects of the earlier steps as to make the resumption of the disease process most improbable, we must know each step from the beginning to the present, understand their sequence and relation, and go back to the beginning with our correction, _removing the cause_. The Cause of Disease Since each event in the morbid process depends upon the preceding one and makes possible those which follow, it is possible to stop at any point in the chain of events and declare, “Here lies the Cause of Disease.” This explains the various etiologies adhered to each by a school of intelligent and scientific men, yet each apparently disagreeing most flatly with the others. No matter which step we select as our “ultimate cause” it truly is the cause, or one of the causes, of succeeding steps, which succeeding steps may well stand in our minds as the whole of the disease. Thus the physician, having found a germ, is quite content to look forward from the invasion of the germ and consider that as the primarily necessary requisite for disease production. In retrospect he follows disease back within the body to the time of entrance of the germ and then leaves the body to study the life habits of the germ and its favorite mode of conveyance. He has unwittingly left the direct line of investigation and followed a spur-track. So with the osteopath who discovers contractured muscles drawing a member, or a bone, from its normal position. He proceeds to a study of the effect of such contracture upon other tissues and strives to relieve it by treatment--of the muscle. The dietist discovers that certain food combinations cannot be properly cared for by an individual and that if taken they tend to develop toxins deleterious to the system. Whereupon he undertakes to discover food combinations which the body _can_ care for and believes that he has solved the question of etiology. Now it is _most_ important that we find the _primary_ cause, the one which makes possible the operation of all the rest and without which all would be powerless to harm man. This we shall expect to find at the point of entrance of disease into the human organism. The primary cause must be the first step _which concerns man_, the first change from normal to abnormal, on which all subsequent changes depend. It is useless to pass outside of the consideration of man and those forces which directly affect man, in our search for the cause of disease. We are powerless to affect outside forces or to control or amend the laws of nature through which disease exists.