THE MEANING OF PERCEPTION 187 



be some nutritional change, a change of bodily form or colouring 

 rendering the animal less conspicuous to its enemies, a sharpened 

 sensation, an increased power of locomotion, a new bodily 

 weapon such as stronger claws or teeth, a new response to the 

 usual stimuli. It may be one of very many kinds of change, but 

 it is always something quite neiv. Some time or other it occurs for 

 the first time in the evolutionary process, and, having occurred, 

 it becomes a habit. 



Reflect upon the discussions of the previous chapters, and it 

 will be seen that we cannot make any clear distinctions anywhere 

 between the " highest " forms of behaviour — that is, the intel- 

 ligently chosen responses to new situations in which we utilise 

 memory and appear to act spontaneously — and the lowest forms, 

 such as those in which an organism acts tropistically. The 

 freely chosen and spontaneous action may become a motor habit, 

 something incorporated in the " make-up " of the animal that 

 evolved it, but so also does the tropism. Between these ex- 

 tremes, the freely chosen activity that involves the utilisation 

 of memory, reflection, and reasoning, and the very simple 

 tropisms there are all gradations — reflex actions, instincts, auto- 

 matic and habitual behaviour, etc. Now can we say that the 

 intelligent action occurring for the first time, and thus accom- 

 panied by or involving perception, is radically different from the 

 tropism, and that when the latter first occurs as a mutation it 

 also is not accompanied by perception ? 



Just because of the continuity in organic form and behaviour 

 that evolution shows us we seem obliged to assume that whenever 

 an animal does something quite new there is perception, which 

 has something in common with that which we call perception in 

 ourselves when we do novel actions. The mutation means that 

 the animal enters into a new relationship with the outer world, 

 and just because it does so it becomes aware of some external 

 things in different aspects from those in which they formerly 

 occurred in its experience. Obviously this appreciation of its 

 new relations with the other world is knowledge, which can, 

 therefore, only be attained when there is action that presents 

 novelty. This, then, is what may be understood by Bergson's 

 saying that theory of life is also theory of knowledge. 



In the new action there is deliberation and choice, the " turn- 

 ing the situation over in the mind," reflection — in short, the 

 application of pure memory (but not motor-habit memory, for 



