126 EVOLUTION AND MAN S PLACE IN NATURE 



in contrast with sensibility. In observation we pass 

 from experience to objects. Observation is impossible 

 without consciousness of the distinction between self 

 and successive experiences : and also of the distinction 

 between experience and external objects. Endless 

 impressions are being made on the senses. Many of 

 these are not observed by us. The organs of sense 

 act exactly as when observations are made ; but no 

 account is taken of the presence and significance of 

 these impressions. Men may gaze together on the 

 same scene, yet in no two cases are the observations 

 the same. It is this difference which creates the 

 interest of conversation concerning places visited. 

 What we need is an exact account of this power of 

 observation, on which all science depends, and by-and- 

 by a scientific account of its appearance in Nature. 

 The first problem is here preparatory for the second. 



Without organs of special sense, observations by 

 sight and sound were impossible ; but, even with these 

 organs, observation involves exercise of a higher power. 

 Hence our double use of terms in describing what 

 seems to us a single exercise. There are obviously 

 two distinct exercises, the one that of the senses, 

 unconsciously executed, the other that of the ra 

 tional power, consciously done. Nevertheless, we take 

 vision as if it were equivalent to observation/ simply 

 because the latter is familiar to us in remarking what 

 is around. Vision belongs to all animals possessing 

 eyes, though observation, in our sense, supplying 

 conditions of observational science, is impossible to 

 animals. We properly attribute sight to the eyes, 

 and an animal sees just as we do ; but there is besides 

 a power in use with us, distinct from the organ of 



