FALLACIES OF SIMPLE INSPECTION. 471 



from an embryo, that eml)ryo itself deriving its origin from ant)lhor 

 plant or animal of the same kind. Again, the thoughts, or reminis- 

 cences, which are effects of our past sensations, resemble those seuBa- 

 tions ; feelings produce similar Ibelings by way of sjnnpathy ; acts 

 produce similai acts by invohuitary or voluntary imitation. With so 

 many appearances in its favor, no wonder if a presumption naturally 

 giew up in men's minds, that causes must ncccssurdi/ resemble their 

 eH'ects, and that like could only be produced by like. 



This principle of fallacy has usually presided over the fantastical 

 attempts to intluence the course of nature by conjectural means, the 

 choice of which was not directed by pievioits obser\'ation and experi- 

 ment. The guess almost always fixed upon some means which pos- 

 sessed features of real or apj)arent resemblance to the end in view. 

 If a charm was wanted, as by Ovid's Medea, to prolong life, all long- 

 lived animals, or what were esteemed such, were collected and brewed 

 into a broth : — 



nee defuit illic 



Squamea Cinyphii tenuis membrana chclydri 



Vivacisque jecur cerv'i : quibps insuper adiiit 



Ora capuique novem cornicis sajcula passaj. 



A similar notion was eml)odied in the celebrated medical theory 

 called the " Doctrine of Signatures," " which is no less," says Dr. 

 Paris,* " than a belief that every natural subtance which possesses 

 any medicinal virtue, indicates by an obvious and well-marked ex- 

 ternal character the disease for which it is a remedy, or the object 

 for which it should be employed." This outward character was 

 generally some feature of rcsomblanco, real or fantastical, cither to 

 the effect it was supposed t(j produce, or to the phenomenon over 

 which its powqr was thought to be exercised. " Thus the lungs 

 of a fox must be a specific for asthma, because that animal is re- 

 markable for its strong powers of resjiiration. Turmeric ha§ a 

 briUiant yellow color, which indicates that it has the power of curing 

 the jaundice ; for the same reason poppies must relieve diseases of the 

 head ; Agaricus those of tlui bladder ; Cassia Jistvfa the affections of 

 the intestines, and Aristolochia the disorders of the uterus: the polish- 

 ed surface and stony hardness which so eminently chiiracterize the 

 seeds of the Llthospermum ofliicinale (common gi'omwell) were deemed 

 a certain indication of their efficacy in calculous and gravelly dis- 

 orders : for a similar reason, the roots of the Saxifraga giamilata 

 (white saxifrage) gained reputation in the cure of the same disease; 

 and the Euphrasia (eye-bright) acquired fame, as an application in 

 complaints of the eye, because it exhibits a black si)ot in its corolla 

 resembling the pupil. The blood-stone, the Heliotropium of the an- 

 cients, from the occasional small specks or points of a blood-red color 

 exhibited on its green surface, is even at this day employed in many 

 parts of England and Scotland, to stop a bleeding from the nose; and 

 nettle tea continues a popular remedy for the cure of Urticaria. It is 

 also asserted that some substances bear the si gnat u res of tlio humors, 

 as the petals of the red rose that of the blood, and the roots of rhubarb 

 and the flowers of saffron that of the bile." 



The early speculations respecting the chemical composition of bodies 

 were rendei-ed abortive by no circumstance more, than by their inva- 



• Pharmacologia, ut supra, pp. 300-7. 



