92 STANDARD OF COMPARISON. 



rather than in the classes represented by the capital letters. If there 

 be no relationship between the mental ability of a child and the age 

 of the father when that child was born, then, according to the law 

 of probabilities, the men of the greatest intellects are just as likely 

 to appear at one part of the scale as at another, and that there is 

 nothing to cause two or more of superior intellectual capacity to 

 appear close together. Conversely, if several men having intellects 

 manifestly superior to others appear close together, and especially 

 if they are grouped at one extreme of the scale, then that fact is 

 explainable only by some cause outside of the law of probabilities. 

 Furthermore, if it should appear that the mental greatness of these 

 men was closely proportional to their relative positions on the scale, 

 that proportional ism could only be explainable on the theory that 

 the inherited mental capacity of a child depends upon the age of the 

 parents at the time the child was born. 



FAME VERSUS MENTAL GREATNESS. 



Before passing from this branch of the subject I must call atten- 

 tion to the fact that fame is not always commensurate with mental 

 greatness. If it were, then Tom Thumb and the Siamese twins 

 would be considered as intellectual giants because they certainly 

 were famous in their day. It is therefore evident that the relative 

 positions of these men in fame is not necessarily their relative 

 positions when we come to consider them purely in respect to their 

 mental powers. In studying these men from the intellectual stand- 

 point we must consider what they have done, and must eliminate 

 from such consideration any halo of glory that depends for its luster 

 on some spectacular achievement. 



