72 THE ORIGIN OF HUMAN REASON. 



ditions, and not such conditions themselves, but they 

 none the less correspond with the orderly arrangement 

 of ideas on the one hand, and of emotional states on the 

 other; being, as Mr. Romanes says, "A reflection of the 

 order or grouping, among the ideas [and feelings] which 

 they are used to express." 



Our author continues : " Even within the region of 

 percepts we meet with a process of spontaneous group- 

 ing of like with like, which, in turn, leads downwards to 

 the purely unconscious or mechanical grouping of stimuli 

 in the lower nerve-centres. So that on its objective face 

 the method has everywhere been the same : whether in 

 the case of reflex action, of sensation, perception, recep- 

 tion, conception, or reflection, on the side of the nervous 

 system, the method of evolution has been uniform ; it 

 has everywhere consisted in a progressive development 

 of the power of discriminating between stimuli, joined 

 with the complementary power of adaptive response." 



How, it may be asked, can Mr. Romanes tell what 

 are the various minute changes in the nervous system 

 which respectively accompany the conscious processes 

 of sensation, perception, conception, and reflection ? It 

 is difficult to understand how he can venture to speak 

 dogmatically on so obscure a subject. The term 

 "discrimination" is commonly applied to denote rather 

 a mental than a mechanical process. That some cor- 

 poreal modification accompanies, in us, every intellec- 

 tual act, we do not for a moment question, and it may 

 be that there is a close analogy between the physical 

 processes in each case. But the passage cited implies 

 much more than this, and is misleading on account of 



