METHODOLOGICAL INTRODUCTION. 21 



fulcrum of the lever ; the result alone is different. Pathologico- 

 chemical phenomena do not originate in the occurrence of new 

 forces or special laws, but merely from the chemical points of 

 application being somewhat different; that is to say, the relations 

 are changed under which the substrata develope their actions of 

 affinity. Pathological phenomena can, therefore, only be recognised 

 when manifested preponderatingly in some one direction, but they 

 of necessity obey one and the same law. As the result of indis- 

 pensable conditions we cannot then regard them as anomalous or 

 abnormal. If protoxide of iron is no longer precipitable by 

 alkalies when organic acids are present, and if fibrin loses its 

 capacity for coagulating in the presence of certain salts, we no 

 more apply the term diseased to these substances than to a clock 

 which stops because the weight has run down. When, in conse- 

 quence of any influence, the capillaries become dilated, and the 

 blood contained in them stagnates, exudes, or coagulates, we 

 do indeed recognise the occurrence of something singular and 

 not of ordinary occurrence, but nothing independent of a law. The 

 physician may designate inflammatory symptoms as abnormal and 

 morbid, but the philosophical enquirer sees only the necessary result 

 of laws acting under different relations, for he has to deal only with 

 fixed laws and not with rules abounding in exceptions. The chemist 

 is an investigator of nature even when occupied in studying patho- 

 logical processes, as the physiologist is still engaged in physiology, 

 when turning his attention to the less frequent phenomena of the 

 living body, for there is no special science for the exceptional phe- 

 nomena of nature but only one physiology as there is one all-powerful 

 law of nature. 



We are tempted, notwithstanding the above observations, to 

 cast a glance at the position occupied by physiological chemistry, in 

 relation to what is called metaphysiology. The recent advances of 

 organic chemistry have unfortunately been interwoven with a fan- 

 tastic physiology, which designates itself as a comparative science. 

 This is not a science comparing together the functions of the 

 organs of different animals, as comparative anatomy compares 

 their structure, but a system founded on abstractions and ideal 

 comparisons ; that is to say, on figurative representations of sub- 

 jective conceptions, in which the results of objective investiga- 

 tion are advanced in defiance of the most contradictory facts. 

 We entertain all due respect for that form of metaphysics which oc- 

 cupies the same rank among the speculative sciences as physiology 

 and chemistry hold among the exact sciences. Metaphysics and 



