200 THE WONDER OF LIFE 



and it remains in process of solution. Almost every 

 modern observer admits that many of the activities of 

 animals, say of bees and wasps, do not conform well with 

 what we know as ordinary intelligent activities. The 

 observed fact is that there is a different ' tang ' about 

 them. The problem is to define this difference, and it 

 may be that one of the reasons why we find this so difficult 

 is, that we are ourselves, predominantly, creatures of 

 intelligence. 



In early days the problem was not clearly focussed. 

 The whole of animal behaviour was slumped, and the whole 

 of human behaviour was slumped two quite unscientific 

 assumptions, and the problem was to find the difference 

 between them. Of course, the man always got the best 

 of it. 



Thus, many of the Greek philosophers, such as Plato, 

 fixed a great gulf betwixt the thinking man and the impulse- 

 driven beast. Man had reason and intelligence, they said ; 

 the animal had sensations and impulses only an anima 

 sensitiva. It is very interesting to observe, however, 

 that Aristotle, while ranking animal behaviour at a much 

 lower level than man's, recognized clearly that it was 

 purposive. 



The conception of instinct, as Nature-implanted impulse, 

 became a little more definite among the Stoics. They 

 compared animals to little children who have not begun 

 to think. Animals have sensations, perceptions, repre- 

 sentations and impulses, they said, but no power of reason- 

 ing. They instanced the case of ducklings hatched and 

 reared by a hen, which show an inborn, Nature-implanted 

 impulse or instinct to make for the water. This was quite 

 sound in its way, but we cannot help wondering what 



