In the 1968 Summer Olympic Games, John Stephen Akhwari of Tanzania was entered in the marathon. He suffered an injury during the race, but he persevered in the darkness on the streets of Mexico City, all alone, as the other runners left him behind. An hour after the race was over, he hobbled into the darkened stadium, his right leg bandaged in two places, grimacing with every step. The few thousand spectators who were lingering in the stadium noticed him and began to applaud as he limped around the track. When h…