Introductory. 7 



in order to have any question to put to the test of 

 objective verification, science must already have so far 

 employed the method of speculation as to have framed 

 a question to be tested ; and, secondly, that the point 

 where science parts company with speculation is the 

 point where this testing process begins. 



Now, if these things are so, there can be no doubt 

 that Darwin was following the truest method of induc- 

 tive research in allowing any amount of latitude to his 

 speculative thought in the direction of scientific theo- 

 rizing. For it follows from the above distinctions that 

 the danger of speculation does not reside in the width 

 of its range, or even in the impetuosity of its vehe- 

 mence. Indeed, the wider its reach, and the greater its 

 energy, the better will it be for the interests of science. 

 The only danger of speculation consists in its momen- 

 tum being apt to carry away the mind from the more 

 laborious work of adequate verification; and therefore 

 a true scientific judgment consists in giving a free 

 rein to speculation on the one hand, while holding 

 ready the break of verification with the other. Now, 

 it is just because Darwin did both these things with 

 so admirable a judgment, that he gave the world of 

 natural history so good a lesson as to the most effec- 

 tual way of driving the chariot of science. 



This lesson we have now all more or less learnt to 

 profit by. Yet no other naturalist has proved himself 

 so proficient in holding the balance true. For the 

 most part, indeed, they have now all ceased to con- 

 found the process of speculation per se with the danger 

 of inadequate verification ; and therefore the old ideal 

 of natural history as concerned merely with collecting 

 species, classifying affinities, and, in general, tabulating 



