574 THE POPULAR SCIENCE MONTHLY 



tematized. It has rather the appearance of a selective action of the 

 drug upon particular nervous elements. The hallucinations of delirium 

 tremens are typical of this. Epilepsy is said to favor hallucinations of 

 blood, fire, and catastrophe ; cocaine, images of a microscopic character. 

 Detailed analyses are apt to be unsatisfactory, owing to the unclear 

 condition of the patient; when the alcoholic reads from or describes in 

 detail the picture on a blank page, he confabulates rather than hallu- 

 cinates. A number of curious clinical observations, such as illusory 

 completion of lost fields in hemianopsia, doubled hallucinations to 

 prisms or pressure, made greater or smaller by opera-glasses, hallucina- 

 tions in one eye or ear only, need be no more than mentioned. 



Hallucinations are reported in all the major psychoses, but for the 

 understanding of the clinical picture, they, and the delusional ideas 

 which supplement them, play the most important role in those types of 

 mental disorder which have been termed biogenetic; that is, where the 

 personality as such fails to meet the normal mental demands of the 

 environment, and reacts to it along certain fairly definite pathological 

 lines. These types of reaction may be for us summed up in the manic- 

 depressive and dementia prcecox groups. A most significant develop- 

 ment in the conception of these conditions is that their basic hallucina- 

 tions and the delusions, whether or not involved with them, are the 

 expressions, not of the selective action of some fortuitous intoxication, 

 but of instinct trends, detached from, or not controlled by, the main 

 personality, and lived out through fantasy. Both Tuttle from the 

 pathological and Cattell from the normal side have indicated how ideas 

 can develop into hallucinations through abnormal reaction to them. 

 These hallucinations and delusions are thus absolutely continuous with 

 normal imagery and imagination, and the minor satisfactions which 

 these latter supply to the normal individual are here magnified to take 

 the place of reality, in response to coercive instincts and desires for 

 whose adjustment reality must be escaped. Are some patients beset 

 by unrecognized erotic longings? The voices horrify them with accu- 

 sations of immorality. Is there some obscure maladaptation in the 

 patient's marriage? The response may be a tragic imagination of the 

 partner's death. The husband who visits his wife is then not her hus- 

 band, but an impostor. Or there may be a fancied alteration of per- 

 sonality, as when under similar circumstances a young man calls him- 

 self at different times " Harry Thaw," " Clarence Richeson," the " king 

 of the fairies." 



Following Cattell's formulation of those higher mental qualities not 

 directly measurable, we should say that defects, particularly of judg- 

 ment, lead to the most serious consequences in general paralysis, arterio- 

 sclerosis, and sometimes in manic excitement. Refinement deteriorates 

 especially in dementia precox and in general paralysis, being, however, 



