pi 



FALLACIES. 



on one another*, as impressions on wax 

 and the like, in which the closest re- 

 semblance between the effect and its 

 cause is the very law of the pheno- 

 menon ; all motion tends to continue 

 itself, with its own velocity, and in its 

 own original direction; and the mo- 

 tion of one body tends to set others 

 in motion, which is indeed the most 

 common of the modes in which the 

 motions of bodies originate. We need 

 scarcely refer to contagion, fermen- 

 tation, and the like ; or to the pro- 

 duction of effects by the growth or 

 expansion of a germ or rudiment re- 

 sembling on a smaller scale the com- 

 pleted phenomenon, as in the growth 

 of a plant or animal from an embryo, 

 that embryo itself deriving its origin 

 from another plant or animal of the 

 same kind. Again, the thoughts or 

 reminiscences which are effects of our 

 past sensations resemble those sen- 

 sations ; feelings produce similar feel- 

 ings by the way of sympathy ; acts 

 produce similar acts by involuntary or 

 voluntary imitation. With so many 

 appearances in its favour, no wonder 

 if a presumption naturally grew up 

 that causes must necessarily resemble 

 their effects, and that like could only 

 be produced by like. 



This principle of fallacy has usually 

 presided over the fantastical attempts 

 to influence the course of nature by 

 conjectural means, the choice of which 

 was not directed by previous observa- 

 tion and experiment. The guess al- 

 most always fixed upon some means 

 which possessed features of real or 

 apparent 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 : — 



.... n«c defuit llllo 



Squamea Cinyphii tenuia membrana 

 ch«lydri 



Vivacisqus j«cur cervi : quibus insup©r 

 addit 



Ora capiitque tiovem coruicia sascula 



pa8S89. 



A similar notion was embodied in 

 the celebrated medical theory called 



the "Doctrine of Signatures," " which 

 is no less," says Dr. Paris,* " than a 

 belief that every natural substance 

 which possesses any medicinal virtue 

 indicates by an obvious and well- 

 inarked external 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 resemblance, real or 

 fantastical, either to the effect it was 

 supposed to produce, or to the pheno- 

 menon over which its power 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 re- 

 spiration. Turmeric has a brilliant 

 yellow colour, which indicates that it 

 has the power of curing the jaundice ; 

 for the same reason, poppies must re- 

 lieve diseases of the head ; Agaricus 

 those of the bladder ; Cassia fistula 

 the affections of the intestines, and 

 Aristolochia the disorders of the 

 uterus : the polished surface and 

 stony hardness which so eminently 

 characterise the seeds of the Litho- 

 spermum officinale (common grom- 

 well) were deemed a certain indica- 

 tion of their efficacy in calculous and 

 gravelly disorders ; for a similar rea- 

 son, the roots of the Saxifraga granu- 

 lata (white saxifrage) gained reputa- 

 tion in the cure of the same disease ; 

 and the Euphrasia (eye -bright) ac- 

 quired fame as an application in com- 

 plaints of the eye, because it exhibits 

 a black spot in its corolla resembling 

 the pupil The bloodstone, the Helio- 

 tropium of the ancients, from the occa- 

 sional small specks or points of a 

 blood-red colour exhibited on its green 

 surface, is even at this very day em- 

 ployed in many parts of England and' 

 Scotland to stop a bleeding from the 

 hoso; and nettle -tea continues a popu- 

 lar remedy for the cure of Urticaria. 

 It is also asserted that some substances 

 bear the signatures of the humours, 

 as the petals of the red rose that of 

 tha bloody and the roots of rhubarb 



* PharmacQlogia, p. 43-45. 



i 



