This depends on the following homoeopathic law of nature which was sometimes, indeed, vaguely surmised but not hitherto fully recognized, and to which is due every real cure that has ever taken place:
A weaker dynamic affection is permanently extinguished in the living organism by a stronger one, if the latter (whilst differing in kind) is very similar to the former in its manifestations.1
1 Thus are cured both physical affections and moral maladies. How is it that in the early dawn the brilliant Jupiter vanishes from the gaze of the beholder? By a stronger very similar power acting on his optic nerve, the brightness of approaching day! – In situations replete with foetid odors, wherewith is it usual to soothe effectually the offended olfactory nerves? With snuff, that affects the sense of smell in a similar but stronger manner! No music, no sugared cake, which act on the nerves of other senses, can cure this olfactory disgust. How does the soldier cunningly stifle the piteous cries of him who runs the gauntlet from the ears of the compassionate bystanders? By the shrill notes of the fife commingled with the roll of the noisy drum! And the distant roar of the enemy’s cannon that inspires his army with fear? By the loud boom of the big drum! For neither the one nor the other would the distribution of a brilliant piece of uniform nor a reprimand to the regiment suffice. In like manner, mourning and sorrow will be effaced from the mind by the account of another and still greater cause for sorrow happening to another, even though it be a mere fiction. The injurious consequences of too great joy will be removed by drinking coffee, which produces an excessive joyous state of mind. Nations like the Germans, who have for centuries been gradually sinking deeper and deeper in soulless apathy and degrading serfdom, must first be trodden still deeper in the dust by the Western Conqueror, until their situation became intolerable; their mean opinion of themselves was thereby over-strained and removed; they again became alive to their dignity as men, and then, for the first time, they raised their heads as Germans.
The curative power of medicines, therefore, depends on their symptoms, similar to the disease but superior to it in strength (§ 12 – 26), so that each individual case of disease is most surely, radically, rapidly and permanently annihilated and removed only by a medicine capable of producing (in the human system) in the most similar and complete manner the totality of its symptoms, which at the same time are stronger than the disease.