Peggy not only crawls now, she goes over obstacles such as arms that are in her way. Playing on the bed, I tried to keep her from the edge by blocking her path with my arm. Since she could crawl over it, I held the arm off the bed at her eye height. Peggy solved this problem quite directly. Reaching out her left hand,, she grabbed my arm by the hair and tilting to the right pulled my arm up and directed it behind her. Of course, I did not want her to fall off the bed, but I didn’t want her well earned success to be simply overpowered. Thus, I grasped her left ankle. Peggy struggled to crawl forward and could not go. She could not diagnose the problem. This impasse continued for several minutes, during which time she turned and looked imploringly at Gretchen once or twice.

This incident marks an example of both her successful and unsuccessful debugging in high contrast.