THEORY OF DISEASE. 



amount of oxygen acting on them in the blood is di- 

 minished. In the sensation of hunger, this resistance, 

 in a certain sense, makes itself known ; and the pre- 

 ponderating vital force exhibits itself, in many patients, 

 when hunger is felt, in the form of an abnormal growth, 

 or an abnormal metamorphosis of certain parts of organs. 

 Sympathy is the transference of diminished resistance 

 from one part, not exactly to the next, but to more 

 distant organs, when the functions of both mutually 

 influence each other. When the action of the diseased 

 organ is connected with that of another ; when, for 

 example, the one no longer produces the matters ne- 

 cessary to the performance of the functions of the other, 

 then the diseased condition is transferred, but only 

 apparently, to the latter. 



In regard to the nature and essence of the vital force, 

 we can hardly deceive ourselves, when we reflect, that 

 it behaves, in all its manifestations, exactly like other 

 natural forces ; that it is devoid of consciousness or of 

 volition, and is subject to the action of a blister. 



The nerves, which accomplish the voluntary and in- 

 voluntary motions in the body, are, according to the 

 preceding exposition, not the producers, but only the 

 conductors of the vital force ; they propagate motion, 

 and behave towards other causes of motion, which in 

 their manifestations are analogous to the vital force, 

 towards a current of electricity, for example, in a pre- 

 cisely analogous manner. They permit the current to 

 traverse them, and present, as conductors of electricity, 



