32 GENERAL EVOLUTION". 



the memory, produces an anticipation of the pain, and the ani- 

 mal at once flies from the source of danger. So, also, with pleasur- 

 able objects, the resultant action being the reverse, or an attraction 

 to the object. In both cases a previous experience of the relation 

 between the object and the sensation of pleasure or pain must have 

 been had. 



There is^ in addition, the power of determining differences and 

 likenesses, by which contiguities or associations are originated in 

 the mind, of a character different from that resulting from the 

 relations of times of receipt of the impression. Such contiguities 

 recall pictures to the consciousness in consequence of their resem- 

 blances in essential qualities. 



On these two bases, together with the perceptive faculties, rest 

 the complex phenomena of the animal and human minds. They 

 are probably physiological functions of brain tissue, for the follow- 

 ing reasons, among others : 



1. Impressions are conveyed by physical means to the brain. 

 The brain can only receive a given number at a time without ex- 

 haustion, and is prepared to receive more after being nourished. 

 Impressions long forgotten are revived in certain states of disease. 

 Impressibility and memory are most marked during growth, and 

 diminish with age. 



2. If impressions are physically produced and preserved in the 

 brain, those made at or near the same time would remain close 

 together in the brain, and this material proximity would be the 

 ^* contiguity " according to which they would come before the 

 consciousness. 



3. Classification or appreciation of resemblances takes place 

 unconsciously in the mind (by '' unconscious cerebration "). Re- 

 semblances not seen at the time of impression suddenly flash into 

 the consciousness on a subsequent revival of it. The " contigu- 

 ity " to like things thus established may be more or less lasting in 

 the mind than the contiguity of circumstances under which the 

 impression was made. 



4. As ^^ contiguity" in time is believed to be revived by 

 contiguity in location of impressions in the ^^i^erceptive" part 

 of the brain, so *^ contiguity " of resemblance may be believed to 

 depend on contiguity of location in the "reflective" part of the 

 brain. 



The retention of the contiguities of time and of resemblance 

 constitute the basis of education of an animal, and its intelligence 



