When I reached home that evening I was regaled by the joyous Jack with an account of his successful battle that afternoon with a mad dog that had attacked him. It was a large, black mongrel, and he had brained it with his ball club. I sounded his emotions. Frightened? Of course; who would not be with a huge mad brute, frothing at the mouth, charging at him? But he had staggered the animal with the first blow, and then had come his courage, his anger, and his furious desire to kill, and save his life. Yes, he had cried, afterward, and was much ashamed of the weakness. But I reassured him on this point, convinced him that strong, brave men sometimes cried under extreme excitement, and in my desire to make the most of the incident in his development, almost overshot the mark. His self-respect became abnormal, and neighboring dogs and small boys suffered, until he was stopped by an experience more salutary than would have been the strapping which his mother and I were seriously contemplating. He attacked another dog, but a sane dog of small size and attending to his business. This dog met the assault bravely and, though suffering keenly from Jack's first blow and unable to injure any living thing larger than a rabbit, offered a strong protest of growls and barks, the moral effect of which was to send the small boy fleeing for home with the small dog snapping at his heels. The neighbors rejoiced, and it was a month before Jack recovered from the humiliation. He did not understand, nor did I until the following day, when his father informed me on the street that the collie, recovered in mind and body, had revenged himself by attacking and biting Jim, who was badly frightened and needed my attention. I could not learn that there was concomitance of time, but I knew that the twins, a mile apart, _shared each other's emotions_. After a fruitless attempt to get legal transfer of Jim to my own household, I fell back on my growing faith in this sympathy of mind, trusting that a careful training of Jack might have a corresponding influence upon Jim. But in this I hoped too much. No such sympathy is ever as strong as daily and personal contact, and the direct and weakening example of that father's life and words worked powerfully upon the character of the boy. His individuality lessened, and as though this lessening were an invitation, the apparently fortuitous incidents and influences of his life became such as to lessen it still further. He seemed to be looking for trouble, and would attempt feats that he failed to perform, while Jack attempted such as were just within his increasing powers. A boy that Jack had pummeled came around and took revenge on Jim. He would yield to pressure that Jack would resist.