A 10-year-old boy decided to study judo despite the fact that he had lost his left arm in a devastating car accident.

The boy began lessons with an old Japanese judo master. The boy was doing well, so he couldn’t understand why, after three months of training the master had taught him only one move. “Sensei,”(Teacher in Japanese) the boy finally said, “Shouldn’t I be learning more moves?” “This is the only move you know, but this is the only move you’ll ever need to...