146 ORGANIC EVOLUTION — MENTAL 



— i. c. reason — in the lower, whereas the reverse is the 

 case ; for in the highest animals — e. g. man — reason 

 predominates, and instinct is at a minimum, while in 

 lower animals — e.g. fish — instinct predominates, and 

 reason is at a minimum. Very plainly, therefore, in 

 higher animals there has been retrogression, not 

 evolution, as regards instinct. Again, instinct and 

 reason do not merge at any point, as they would were 

 one derived from the other. The fact that one is 

 inborn and the other acquired separates them sharply, 

 and if, in the case of any given action, which is the 

 outcome both of instinct and reason, as, for instance, a 

 man's choice of a wife, we are unable to say how much 

 of it is instinctive, and how much rational, our 

 difficulty is due to our ignorance, not to there being no 

 dividing line, but a border-space. 



According to Mr. Spencer, " rational action arises out 

 of instinctive action when the latter grows too complex 

 to be perfectly automatic " {Principles of Fsyeliologij, 

 vol. i. p. 458). His hypothesis, like Mr. Lewes', 

 necessarily involves the supposition that there is a 

 border-space where the instinctive and the rational 

 merge. We have seen that he defines instinct as 

 compound reflex action. In his view, therefore, rational 

 action is reflex action still more highly compounded. 

 Concerning instinct he says — 



" In its higher forms, instinct is probably accompanied 

 by a rudimentary consciousness. There cannot be co- 

 ordination of many stimuli without some ganglion 

 through which they are all brought into relation. In 

 the j)rocess of bringing them into relation, this ganglion 

 must be subject to the influence of each — must undergo 

 many changes. And the quick succession of changes 

 in the ganglion, implying as it does j)erpetual experi- 

 ences of differences and likenesses, constitutes the raw 

 material of consciousness. The implication is, that as 



