188 THE GENESIS OF SCIENCE. 



haps our argument may be best initiated by the proposi 

 tion, that all intelligent action whatever depends upon the 

 discerning of distinctions among surrounding things. The 

 condition under which only it is possible for any creature 

 to obtain food and avoid danger is, that it shall be differ 

 ently affected by different objects that it shall be led to 

 act in one way by one object, and in another way by 

 another. In the lower orders of creatures this condition is 

 fulfilled by means of an apparatus which acts automatically. 

 In the higher orders the actions are partly automatic, 

 partly conscious. And in man they are almost wholly 

 conscious. 



Throughout, however, there must necessarily exist a 

 certain classification of things according to their properties 

 a classification which is either organically registered in 

 the system, as in the inferior creation, or is formed by 

 experience, as in ourselves. And it may be further re 

 marked, that the extent to which this classification is 

 carried, roughly indicates the height of intelligence that, 

 while the lowest organisms are able to do little more than 

 discriminate organic from inorganic matter ; while the 

 generality of animals carry their classifications no further 

 than to a limited number of plants or creatures serving 

 for food, a limited number of beasts of prey, and a limited 

 number of places and materials ; the most degraded of the 

 human race possess a knowledge of the distinctive natures 

 of a great variety of substances, plants, animals, tools, per 

 sons, &amp;lt;fcc., not only as classes but as individuals, 



What now is the mental process by which classification 

 is effected ? Manifestly it is a recognition of the likeness 

 or unlikeness of things, either in respect of their sizes, 

 colours, forms, weights, textures, tastes, &c., or in respect 

 of their modes of action. By some special mark, sound, or 

 motion, the savage identifies a certain four-legged crea 

 ture he sees, as one that is good for food, and to be caught 



