REASONABLE BUT UNREASONING 



lets out the sawdust, as I have often known him to 

 do, what does he act like then ? 



Such instances reveal as by a flash of light the 

 nature of animal mentality — how blindly, how 

 automatically, the beasts act. If a person ever be- 

 haved in that way, we should say he had lost his 

 mind, that reason was dethroned. We should not 

 merely say he was unreasonable, we should say he 

 was insane. 



In its ordinary course of life the animal behaves 

 in a reasonable manner, its course of action follows 

 regular lines. Its progenitors have followed the 

 same lines for countless generations ; habit has worn 

 a groove. But when a new, unheard-of condition 

 confronts them, then there is no groove and their 

 activity takes these irrational forms. When the 

 phoebe-bird covers her nest in the ledge with moss, 

 she does a reasonable thing; she blends it with the 

 rock in a way that is both good art and good strategy. 

 Now, if this were the result of reason, when she 

 comes to the porch and to newly hewn timbers she 

 would leave the moss off, because here it betrays 

 rather than conceals her nest. But she sticks to her 

 moss wherever she goes. 



The same curious blundering may be seen in the 

 insect world. For instance, the trap-door spiders in 

 California make their nests in moss-covered ground 

 and cover the lids of the doors with green growing 

 moss. An English naturalist, as reported by Jordan 

 183 



