ANIMAL INTELLIGENCE. 215 



should find, that, although no two of them are exactly alike, they all 

 bear a certain general resemblance to one another. Thus from the 

 multitude of faces which I now perceive it becomes possible for my 

 mind to abstract from them all the essential qualities of a face as a 

 face ; and such a mental abstraction of qualities would then constitute 

 what I might call my abstract idea of a face in general, as distinguished 

 from my concrete idea, or memory, of any face in particular. 



Thus, then, we have three stages : 1. That of immediate percep- 

 tion; 2. That of ideal representation of particular objects; and, 3. 

 That of a generalized conception, or abstract idea, of a number of 

 qualities which a whole class of objects agree in possessing. It will 

 be convenient to split the latter division into two subdivisions, viz., 

 abstract ideas which are sufficiently simple to be developed without 

 the aid of language, and abstract ideas which are so complex as not 

 to admit of development without the aid of language. As an instance 

 of the former class of abstract ideas we may take the idea of food. 

 This is aroused in our minds by the feeling of hunger ; and, while the 

 idea when thus aroused is clearly quite independent of language, it is 

 no less clearly what is called an abstract idea. For it is by no means 

 necessary that the idea of food which is present to the mind should be 

 the idea of some special kind of food ; on the contrary, the idea is usu- 

 ally that of food in general^ and this idea it is which usually prompts 

 us to seek for any kind of food in particular. Simple abstract ideas, 

 therefore, may be formed without the assistance of language ; and for 

 this reason they are comprised within what has been called the Logic 

 of Feelings. But abstract ideas of a more elaborated type can only be 

 formed by the help of words, and are therefore comprised within what 

 has been called the Logic of Signs. The manner in which language 

 thus operates in the formation of highly-abstract ideas is easily ex- 

 plained. Because we see that a great many objects present a certain 

 quality in common, such as redness, we find it convenient to give this 

 quality a name ; and having done this we speak of redness in the ab- 

 stract, or as standing apart from any particular object. Our word 

 *' redness " then serves as a sign or symbol of a quality as apart from 

 any particular object of which it may happen to be a quality ; and 

 having made this symbolical abstraction in the case of a simple quality, 

 such as redness, we can afterward compound it with other symbolical 

 abstractions, and so on till we arrive at verbal symbols of more and 

 more complex qualities, as well as qualities further and further removed 

 from immediate perception. By the help of these symbols, therefore, 

 we climb into higher and higher regions of abstraction ; by thinking in 

 verbal signs, we think, as it were, with the semblance of thoughts, and 

 by combining these signs in various ways, and giving the resulting 

 compounds distinctive names, we are able to condense into single 

 words, or signs, an enormous amount of meaning. So that, just as in 

 mathematics the symbols which are employed contain, in an easily 



