EVOLUTION AND DISSOLUTION. 177 



8. So far I have spoken of local dissolution occurring on but one- 

 half of the nervous system on different levels. Coming to the highest 

 centers I speak of uniform dissolutions — of cases in which all divisions 

 of these centers are subjected to the same evil influence. I choose some 

 cases of insanity. In doing this I am taking uj) the most diflicult of 

 all nervous diseases. I grant that it is not possible to show in detail 

 that they exemplify the principle of dissolution, but choosing the sim- 

 plest of these most complex cases we may show clearly that they illus- 

 trate it in general. I take a very commonplace example — delirium in 

 acute non-cerebral disease. This, scientifically regarded, is a case of 

 insanity. In this, as in all other cases of insanity, it is imperative to 

 take equally into account not only the dissolution but the lower level 

 of evolution that remains. The patient's condition is jDartly negative 

 and partly positive. Negatively, he ceases to know that he is in hos- 

 pital, and ceases to recognize persons about him. In other words, he 

 is lost to his surroundings, or, in equivalent terms, he is defectively 

 conscious. We must not say that he does not know where he is be- 

 cause he is defectively conscious ; his not knowing where he is, is 

 itself defect of consciousness. The negative mental state signifies, on 

 the physical side, exhaustion, or loss of function, somehow caused, of 

 some highest nervous arrangements of his highest centers. We may 

 conveniently say that it shows loss of function of the topmost layer of 

 his highest centers. No one, of course, believes that the highest centers, 

 or any other centers, are in layers ; but the sujDposition will simplify 

 exposition. The other half of his condition is positive. Besides his 

 not knowings, there are his wrong knowings. He imagines himself to 

 be at home or at work, and acts as far as practicable as if he were ; 

 ceasing to recognize his nurse as a nurse, he takes her to be his wife. 

 This, the positive pai't of his condition, shows activity of the second 

 layer of his highest centers ; but which, now that the normal topmost 

 layer is out of function, is the then highest layer ; his delirium is the 

 " survival of the fittest states," on his then highest evolutionary level. 

 Plainly, he is reduced to a more automatic condition. Being (nega- 

 tively) lost, from loss of function of the highest, latest developed, and 

 least organized, to his present " real " surroundings, he (positively) 

 talks and acts as if adjusted to some former " ideal " surroundings, 

 necessarily the more organized. 



I now make some general remarks on the eight illustrations, in 

 order to prevent certain misunderstanding. It is asserted, again, that 

 each of the eight cases is a different dissolution. All that is meant is 

 that each shows a reduction from the voluntary toward the automatic 

 in what the center, or part of it, which is diseased, represents. If we 

 take extreme cases, the case of progressive muscular atrophy and the 

 case of insanity (delirium in acute non-cerebral disease), we say that 

 the two are alike, because in each there is reduction to a more au- 

 tomatic condition, and we say, too, that they are very unlike, the 



VOL. XXV. — 12 



