Aphorism 64

During the primary action of the artificial morbific agents (medicines) on our healthy body, as seen in the following examples, our vital force seems to conduct itself merely in a passive (receptive) manners, and appears, so to say, compelled to permit the impressions of the artificial power acting from without to take place in it and thereby after its state of health; it then, however, appears to rouse itself again, as it were, and to develop (A) the exact opposite condition of health (counteraction, secondary action) to this effect (primary action) produced upon it, if there be such an opposite, and that in as great a degree as was the effect (primary action) of the artificial morbific agent on it, and proportionate to its own energy; - or (B) if there be not in nature a state exactly the opposite of the primary action, it appears to endeavor to indifferentiate itself, that is, to make its superior power available in the extinction of the change wrought in it from without (by the medicine), in the place of which it substitutes its normal state (secondary action, curative action).