xii ARTICULATE IDEAS 297 



On the other hand, comparative psychology cannot 

 afford altogether to neglect the casual observation. It 

 must be borne in mind that the little combinations of 

 experience which are in question, are, to the animal, if 

 they exist at all, what a new invention is to the human 

 being. When sufficiently clear and pronounced to strike 

 the observer, they would naturally be rarities, occurring 

 only now and then under favourable conditions, internal 

 and external. Such conditions are likely to occur only 

 when the animal is at work on its own ground. They 

 are less probable when we set the animal to work at a task 

 of our choosing. Lastly, it must be added that the body 

 of evidence of this kind is too considerable to be 

 altogether ignored. There appear to be in the ordinary 

 works on natural history and animal psychology, a great 

 number of instances of " animal sagacity " which are 

 impossible if we suppose the learning of animals limited 

 to the formation of habits or associations, but are readily 

 intelligible if we grant them the power of forming practical 

 ideas on the basis of experience, and of appropriately 

 selecting and combining such ideas to meet the pressure 

 of practical needs in the circumstances of the moment. 



I will not go through the mass of this evidence, but 

 may take one or two cases as typical. 1 have referred 

 above to stories such as those given in General Hutchin- 

 son's book Dog Breaking, 1 of dogs running round 

 game when they found that the game, instead of rising, 

 ran before them. Clearly, this is a violation of habit, and 

 is unintelligible if we suppose the dog to act without the 

 purpose of making the birds rise. On the other hand, no 

 abstract idea : no general plan : no universal conception 

 is required. Grant that the dog wants to get these birds 

 up, and that past experience will enable him to form a 

 concrete judgment as to how they will act, and we have 

 all the conditions that we need. What is postulated is, 

 concrete experience, present purpose, and the interaction 

 of the results of experience with present perception to 

 form a combination or adaptation of actions suitable to 

 the needs of the moment. 



1 See p. 264. 



