162 Darwinism and Other Essays. 



the faculties of men do not improve. It is in or- 

 der to do this that he rejects the law of transmis- 

 sion. But it has been shown that his rejection of 

 it is illogical, and that the law of transmission is 

 as universal as any other, since, were it not so, 

 there could be no such thing as a species at all. 

 With the help of this law, it is easy to demon- 

 strate that, in the very nature of things, the fac- 

 ulties of men must improve. 



Among that "highest class of biological truths," 

 which apply to all organisms whatever, is the law 

 that, " other things equal, development varies as 

 function ; " l that is, the growth of any organ de- 

 pends upon its activity. We are everywhere met 

 by instances of this: not only in the gymnast, 

 who surprises us by the great size and power of 

 his muscles ; not only in the sailor, who sees a 

 ship in the distant offing, when the passenger can 

 descry but a speck; not only in the musician, 

 who recognizes as different two sounds which to 

 unpractised ears are alike ; but also in the man 

 of science, who unravels with ease problems which 

 to common apprehensions are insoluble. " On 

 this law are based all maxims and methods of 

 right education, intellectual, moral, and physical." 2 

 Expressed in the form, " Practice makes perfect,* 



1 Spencer's Essays, o. 262. 2 Ibid, p. 263. 



