On the Inheritance of the Mental Characters in Man. 155 



with the physical was occupying our attention in another field, the 

 indefatigable Dr. Lee undertook the tabulation and calculation of 

 the coefficients of heredity in the case of seven mental and three 

 physical characters for pairs of brothers. The number of pairs dealt 

 with in each case were 800 to 1000. The method adopted was that of 

 the memoir on " The Inheritance of Characters not capable of Exact 

 Quantitative Measurement."* Thus, under the heading Conscientiousness 

 were two divisions, Keen and Dull, and the teacher might place a cross 

 on either of these or on the dividing line. Similar divisions occurred 

 in the other categories, except that Intelligence was given six and 

 Temper three subdivisions, &c. The collecting schedules will be fully 

 described when the whole bulk of material is finally reduced and 

 published. My sole object in the present preliminary notice is to 

 draw attention to the following results : 



Coefficients of Collateral Heredity. 

 Correlation of Pairs of Brothers. 



Physical Characters. Mental Characters. 



(Family Measurements.) (School Observations.) 



Stature '5107 Intelligence -4559 



Forearm 0'4912 Vivacity -4702 



Span, 0'5494 Conscientiousness '5929 



Eye-colour 0'5169 Popularity 0'5044 



Temper '5068 



(School Observations.) Self-consciousness 0'5915 



Cephalic index 0"4S6i Shyness '5281 



Hair-colour "5452 



Health . . '5203 



Mean -5171 Mean 0'5214 



The physical characters were measured or observed on two entirely 

 different groups of individuals in the one case, adults, in the other, 

 children, were examined. Both groups, however, give very like mean 

 results, i.e., 0'5170 and 0'5172. Dealing with the means for physical 

 and mental characters we are forced to the perfectly definite conclu- 

 sion : That the mental characters in man are inherited in precisely the same 

 manner as the physical. Our mental and moral nature is, quite as much 

 as our physical nature, the outcome of hereditary factors. 



The probable error of the coefficients given is about 0*02 at most ; 

 the differences between the individual values and their significance 

 will be fully considered in the final memoir. 



* ' Phil. Trans.,' A, vol. 195, pp. 79-150. 



