154 THE DESCENT OF MAN 



A man cannot prevent past impressions often repassing 

 through his mind; he will thus be driven to make a com- 

 parison between the impressions of past hunger, vengeance 

 satisfied, or danger shunned at other men's cost, with the 

 almost ever-present instinct of sympathy, and with his early 

 knowledge- of what others consider as praiseworthy or blama- 

 ble. This knowledge cannot be banished from his mind, 

 and from instinctive sympathy is esteemed of great moment. 

 He will then feel as if he had been balked in following a 

 present instinct or habit, and this with all animals causes 

 dissatisfaction, or even misery. 



The above case of the swallow affords an illustration, 

 though of a reversed nature, of a temporary, though for 

 the time strongly persistent, instinct conquering another in- 

 stinct which is usually dominant over all others. At the 

 proper season these birds seem all day long to be impressed 

 with the desire to migrate; their habits change; they be- 

 come restless, are noisy, and congregate in flocks. While 

 the mother-bird is feeding, or brooding over her nestlings, 

 the maternal instinct is probably stronger than the migra- 

 tory; but the instinct which is the more persistent gains 

 the victory, and at last, at a moment when her young ones 

 are not in sight, she takes flight and deserts them. When 

 arrived at the end of her long journey, and the migratory 

 instinct has ceased to act, what an agony of remorse the 

 bird would feel, if, from being endowed with great mental 

 activity, she could not prevent the image constantly passing 



seem to he innate, and is certainly a most persistent one. It seems to be the 

 complement and converse of the true social instinct. From what we hear of 

 savages, it would appear that something of the same kind holds good with 

 them. If this be so, it would be a small step in any one to transfer such feel- 

 ings, to any member of the same tribe if he had done him an injury and had 

 become his enemy. Nor is it probable that the primitive conscience would re- 

 proach a man for injuring his enemy : rather it would reproach him if he had not 

 revenged himself. To do good in return for evil, to love your enemy, is a height 

 of morality to which it may be doubted whether the social instincts would, by 

 themselves, have ever led us. It is necessary that these instincts, together 

 with sympathy, should have been highly cultivated and extended by the aid of 

 reason, instruction, and the love or fear of G-od, before any such golden rule 

 would ever be thought of and obeyed. 



