In a brief but very excellent article on therapeutic action by Dr. Thomas J. Mays, of Philadelphia, in the AMERICAN THERAPIST, he commences thus: “Every phenomenon in nature becomes intelligible only when considered in the light of force. Any scientific system of therapeutics must therefore be built on a broader basis than that of the mere drug action on the animal economy.” In this he is unquestionably correct; but when he, along with others, asserts that drug action is due to what is termed “interference,” to me, at least, he becomes unintelligible. I am utterly unable to take in the idea. When he refers it to molecular motion, which, after all, is chemical change, he is right. Heat, light, electricity, motion—each interchangeable, correlating with each other, constituting force—must be the source of all chemical action. These are, strictly speaking, proteodynamics. They act, as I have indicated, upon the cell. This action may be either metabolic or katabolic, and when the remedial agent is presented the change results. So true is this that the _vis vitæ_ itself results from chemism, so that every action, every change, has simply two factors—matter and dynamism. In this connection permit me to make the following quotation from the _Medical News_: “Of course, it had been recognized that certain diseases are self-limited, and the phenomena of natural and acquired immunity were duly appreciated; but it required the knowledge gained by the advances in bacteriology to afford a rational explanation of these phenomena. There is yet much to learn. The beginning has but been made. Enough, however, has been seen to teach that disease has its chemistry, and that the treatment of the future will depend upon a knowledge of this fact and the application of chemic laws.”