The Doctrine of Signatures
was at least intelligible. It associated itself, too, with the pious utterances so frequent among the mediæval teachers and practitioners of medicine. The theory was that the Creator in providing herbs for the service of man had stamped on them, at least in many instances, an indication of their special remedial value. The adoption of ginseng root by the Chinese as a remedy for impotence, and of mandrake by the Hebrews and Greeks in the treatment of sterility, those roots often resembling the male form, have been often cited as evidence of the antiquity of the general dogma. . . . But isolated instances of that kind are very far from proving the existence of systematic belief. Hippocrates states that diseases are sometimes cured by the use of "like" remedies; but he was not the founder of homœopathy.
It is likely that the belief in a special indication of the virtues of remedies grew up slowly in the monasteries, and was originated, perhaps, by noticing some curious coincidences. It found wide acceptation in the sixteenth century, largely owing to the confident belief in the doctrine expressed in the writings of Paracelsus. Oswald Crollius and Giovanni Batista Porta, both mystical medical authors, taught the idea with enthusiasm. But it can hardly be said that it maintained its influence to any appreciable extent beyond the seventeenth century. Dr. Paris describes the doctrine of signatures as "the most absurd and preposterous hypothesis that has disgraced the annals of medicine"; but except that it may have led to experiments with a few valueless herbs, it is difficult to see sufficient reason for this extravagant condemnation of a poetic fancy.
