vi INSTINCT 79 



involves, we saw, attentive concentrated perception. In 

 us this is a consciousness. In the animal under the same 

 circumstances we see all the corresponding outward signs, 

 the pricked ear, the sniffing nose, the fixed eyeball, the 

 tense musculature ; we have also corresponding ante- 

 cedents and corresponding consequences. There must, 

 therefore, be some state of the animal's organism corres- 

 ponding in causes, expression, and functions to our 

 attentive perception, and though that state cannot be 

 more directly known to us, we describe it in accordance 

 with our avowed method by the same name. Now we 

 have to ask what determines attentive perception, and 

 what causes it to discharge actions of a particular kind. 

 The answer in our case is that (apart from the intensity 

 or other peculiarity of some external stimulus) there is 

 some interest which directs perception, is served by the 

 response which the perception discharges, and is in fact 

 the motive force behind the perception. This interest 

 does not necessarily form an independent state of con- 

 sciousness, but it qualifies our consciousness as long as it 

 lasts, giving our conscious perception an emotional 

 tinge and impregnating it with the sense of effort and 

 excitement. Now such an interest may be connected 

 with a conscious purpose and may arise out of experience. 

 But there is no difficulty in conceiving a similar interest 

 as an innate or hereditary disposition brought into action 

 by an appropriate situation as stimulus or possibly even 

 in the course of the purely internal changes of the 

 organism. Precisely such a state so arising, so enduring 

 till its function is performed, and so directing the series 

 of constituent actions is what we find in Instinct. 



To this direction Instinct mainly owes it plasticity of 

 adjustment. As we ascend the scale this feature develops 

 and the divergence from the reflex type becomes more 

 pronounced. Alternative methods of action are used and 

 used appropriately. Different kinds of reaction are 

 combined in ways that must vary, more or less, from 

 case to case. Lastly within certain limits special obstacles 

 or deviations from the normal course of events seem to 

 call up special reactions fitted to deal with them. This 



