CHAP. XIV.] PSYCHOPHYSIK. 457 



upon our earth, an insuperable limit was marked; while 

 upwards from this to the most elevated mental activity, and 

 downwards from the vital force of the organic to the simple 

 physical force, he nowhere finds another limit." 



To this Professor Nageli replies 



" Experience shows that from the clearest consciousness 

 of the thinker downwards, through the more imperfect con- 

 sciousness of the child, to the unconsciousness of the embryo, 

 and to the insensibility of the human ovum, or through 

 the more imperfect consciousness of undeveloped human 

 races and of higher animals to the unconsciousness of lower 

 animals and of sensitive plants, and to the insensibility of 

 all other plants, there exists a continuous gradation without 

 definable limit, and that the same gradation continues from 

 the life of the animal ovum and the vegetable cell down- 

 wards, through organised elementary and more or less lifeless 

 forms (parts of the cell), to crystals and chemical molecules." 



Professor von Nageli accepts the fact of sensation, appe- 

 tency, and thought in the higher forms of life ; but instead 

 of trying to resolve it into a mechanical process, he levels up 

 the discontinuity of the chain of being by attributing sensa- 

 tion not only to all organisms, but also to all cells, molecules, 

 and atoms. This is what he says 



" Now, if the molecules possess anything which is ever 

 so distantly related to sensation, and we cannot doubt it, 

 since each one feels the presence, the certain condition, the 

 peculiar forces of the other, and, accordingly, has the 

 inclination to move, and under circumstances really begins 

 to move becomes alive as it were ; moreover, since such 

 molecules are the elements which cause pleasure and pain ; 

 if, therefore, the molecules feel something that is related to 

 sensation, then this must be pleasure, if they can respond 

 to attraction and repulsion, i.e. follow their inclination or 

 disinclination ; it must be displeasure if they are forced to 

 execute some opposite movement, and it must be neither 

 pleasure nor displeasure if they remain at rest." 



Professor von Nageli is what Professor Huxley would call 

 a mere biologist, or he would have known that the molecules, 



