The stories, which seem to be well authenticated, of sheep-killing dogs that have slipped their collars in the night and indulged their passion for live mutton, and then returned and thrust their necks into their collars before their absence was discovered, do not, to my mind, prove that the dogs were trying to deceive their masters and conceal their guilt, but rather show how obedient to the chain and collar the dogs had become. They had long been subject to such control and discipline, and they returned to them again from the mere force of habit. I do not believe even the dog to be capable of a sense of guilt. Such a sense implies a sense of duty, and this is a complex ethical sense that the animals do not experience. What the dog fears, and what makes him put on his look of guilt and shame, is his master's anger. A harsh word or a severe look will make him assume the air of a culprit whether he is one or not, and, on the other hand, a kind word and a reassuring smile will transform him into a happy beast, no matter if the blood of his victim is fresh upon him. A dog is to be broken of a bad habit, if at all, not by an appeal to his conscience or to his sense of duty, for he has neither, but by an appeal to his susceptibility to pain. Both Pliny and Plutarch tell the story of an elephant which, having been beaten by its trainer for its poor dancing, was afterward found all by itself practicing its steps by the light of the moon. This is just as credible as many of the animal stories one hears nowadays. Many of the actions of the lower animals are as automatic as those of the tin rooster that serves as a weather-vane. See how intelligently the rooster acts, always pointing the direction of the wind without a moment's hesitation. Or behold the vessel anchored in the harbor, how intelligently it adjusts itself to the winds and the tides! I have seen a log, caught in an eddy in a flooded stream, apparently make such struggles to escape that the thing became almost uncanny in its semblance to life. Man himself often obeys just such unseen currents of race or history when he thinks he is acting upon his own initiative. When I was in Alaska, I saw precipices down which hundreds of horses had dashed themselves in their mad and desperate efforts to escape from the toil and suffering they underwent on the White Pass trail. Shall we say these horses deliberately committed suicide? Suicide it certainly was in effect, but of course not in intention. What does or can a horse know about death, or about self-destruction? These animals were maddened by their hardships, and blindly plunged down the rocks.