38o REFLEX ACTION, INSTINCT, AND REASON 



tive emotions. But, though intelligence is altogether an acquire- 

 ment, I think no one will deny that we speak correctly when we say 

 that it has undergone evolution in the higher animals. Like many 

 instincts and physical characters, it arises late in the development 

 of the individual (for it arose late in the evolution of the species), 

 but it is none the less as essential a part of his mental growth as 

 any trait which arises under the stimulus of nutriment. In fact, 

 though students of the subject have never realised that intelligence 

 is an acquirement, yet it has been universally recognised that the 

 mental evolution of the higher animals has consisted mainly in 

 the evolution of intelligence and reason that is, as we see when 

 we think closely, of the evolution of memory and of the mental 

 growth which the possession of memory renders possible. 



630. Family life, which is practised by all the higher animals, is 

 not only a product of memory but is also that which has rendered 

 possible the evolution of a voluminous memory. The offspring are 

 recognized by the mother, and in the case of some animals by 

 the father who then recognises his mate also. This recognition 

 implies some degree of memory and consequently intelligence. 

 The young, instead of being cast adrift at birth to fend for them- 

 selves, are watched and protected, and, by the highest animals, 

 taught. Time and opportunity are thus afforded for learning about 

 the world, and, more particularly, of acquiring the traditions, the 

 stored experiences of the race. Animals which have no family 

 life, for example most fish, amphibians (e.g. frogs), and reptiles, 

 may possess a memory, but it is always very rudimentary. They 

 may learn a little from experience, but only a very little; their 

 intelligence is very low, their thoughts must be few and simple. 

 The recognition of offspring by parents is usually, but erroneously 

 assumed to be instinctive. It is certainly acquired through experi- 

 ence after the birth. But once the child is known, the more 

 intelligent the animal the more perfect is the subsequent recogni- 

 tion. The hen will adopt strange eggs and chickens, and even 

 ducklings and pea chicks. The ewe, the cow, and the human 

 mother may have strange offspring foisted on them immediately 

 after parturition, but they are not easily deluded after they have 

 performed the first offices of tenderness. 



631. With the opportunity which parental protection affords to 

 the young to profit by experience comes the ability to profit by it, 

 and with the latter a proportionate retrogression of now useless 

 instincts. Intelligence is substituted for unthinking impulse. All 

 the instincts are not lost, but in the higher animals we find no such 



