742 THE POPULAR SCIENCE MONTHLY. 



" Introspection will convince us — perhaps to our own astonish- 

 ment — how large a part of our thinking operations are conducted 

 through the raising and recalling of remembered images." * 



But it may be objected that one can not spend one's time in 

 day-dreams, or in the mere pleasures of memory and imagination. 

 You say that reason and action are the real things of life. Have 

 these, too, such a physical as well as a mental basis ? Let us fol- 

 low one or two simple acts of reasoning for a moment. When you 

 see a rose, although it is at a distance from you, you will admit 

 that you believe it to have a fragrance. You conclude that it has, 

 because in your former experience with roses you remember that, 

 when you have held one near, you have always perceived its per- 

 fume. The association of the sight of the rose and the fragrance 

 has become fixed in your mind, and when you see it your thought 

 is led along to its fragrance, and you draw the conclusion that the 

 rose is fragrant. That is an act of reasoning. Supposing some 

 one says that the rose sounds sweetly. You have no association 

 between such things as roses and sounds in nature, and your 

 thought refuses to run along where there is no track. You reply 

 that he is talking nonsense — that is, the unreasonable. 



Or take another example. Your dog sees you go into the hall 

 and take up your hat and cane ; he at once jumps up and runs 

 about, showing by his action that he has come to the conclusion 

 that you are off for a walk, and that he wants to go with you. 

 What is the basis of this process of reasoning ? He has a mental 

 image of this act of yours, associated with another mental image 

 of a run on the lawn, and the first calls up to his mind the second. 

 In his experience one act has usually followed the other, and he 

 draws the conclusion that you are going out where he can run. 

 You say at once that the dog has reasoned correctly. It may 

 even be true that the dog has learned to understand language. 

 Many dogs know the word " out," and it calls up to them as dis- 

 tinct a mental image as your act of putting on your hat. Sir 

 John Lubbock has even taught his dog to read ; f for, by showing 

 him a large card on which the word " water " was printed, every 

 time he gave him a drink, an association was established in the 

 dog's mind between the card and the act ; and, finally, when the 

 dog wanted a drink, he would bring the card in his mouth to his 

 master. Ten such different words were taught him, and he rarely 

 made a mistake. So that the understanding of speech and of 

 writing and the act of reasoning, so far as simple conclusions go, 

 from the recollection of mental images, may be granted to ani- 

 mals as well as to man. And these acts of reasoning, like those 



* Argyll, " The Identity of Thought and Language," " Contemporary Review," De- 

 cember, 1 888, p. 814. 



f " Intelligence of Animals," D. Applcton & Co. 



