INHERITANCE OF TEMPERAMENT. 95 



V. DISCUSSION OF EARLIER STUDIES ON HEREDITY OF 



TEMPERAMENT. 



The earliest and, so far as I know, the only previous attempt to 

 analyze the hereditary factors in temperament in general was made by 

 Galton (1889, pp. 226-238). But his group of "bad temper" included 

 such opposite moods as "choleric," "decisive," "fits of anger," "head- 

 strong," and "impetuous" on the one hand, and "gloomy," "morose," 

 "sullen," on the other. His group of "good temper" includes not 

 only calm, equable, placid, self -controlled (our "normal"), but also 

 "amiable" and "buoyant" (our "nervous"), and also submissive and 

 timid (probably phlegmatic). With such an unfortunate association of 

 dissimilars it is not strange that he did not get clear-cut results. Where 

 both parents are "good-tempered" 30 per cent of the children were 

 "good-tempered" and 10 per cent bad-tempered; the rest (60 per 

 cent) being of neutral temper. Where both parents were "bad-tem- 

 pered," 4 per cent were good and 52 per cent bad-tempered, 44 per 

 cent being neutral. Just what neutral means is not explained; prob- 

 ably it includes two groups — those of mixed temperaments and those 

 whose temperament is not fully given. On the other hand, many 

 studies have been made on emotional insanity, i. e., of the manic- 

 depressive group. That insanity of the emotional group is inherited 

 has long been recognized. Burrows (1820, p. 9) says: 



"There certainly is no physical error in accounting insanity hereditary. 

 Had the knowledge of this fact merely led to a closer inquiry respecting those 

 with whom a connubial union is contemplated, it would be a commendable 

 foresight, often conducing to the preservation of domestic bliss now too 

 frequently interrupted by the development of this dreadful affliction in the 

 object, perhaps, of our tenderest affections." 



Lucas (1850) devoted a considerable part of his work to heredity of 

 mental disorders, and in the latest edition of his Psychiatrie, Kraepelin 

 (1909) devotes over 10 pages to heredity, and gives a brief bibliography 

 of writings on the subject from 1893 to 1907. Kraepelin observes that : 



"The various forms of mental ailment are influenced in very different degree 

 by the hereditary factor. Its action is naturally most evident in those dis- 

 turbances that arise from internal causes. Here belong manic-depressive 

 insanity, the epileptic and hysterical mental disturbances, moreover , nervous- 

 ness, obsessions, impulsions, sexual perversions, the different forms of diseased 

 personalities; finally, also, paranoia." 



The circumstance that manic-depressive insanity is regarded as 

 being more "influenced by heredity" than dementia precox would 

 suggest that it, or some of its elements, are dominant. Rosanoff and 

 Orr (191 1) entertained the hypothesis that the so-called functional 

 psychoses may be considered to depend upon a single heredity factor, 

 and their data seem to support strongly the hypothesis. The paper 

 marks a great advance because of the quality of the data and the 

 method of analysis. Rosanoff reached the conclusion that the func- 



