In the illumination of his mind Adam saw much that had been mystery to him. When he had hunted meat, why had the chase been thrilling, exciting, pressing his heart hot against his side, sending his blood in gusts over his body? What a joy to run and leap after the quarry! Strange indeed had been his lust to kill beasts when, after killing, he was sorry. Stranger than this was a fact keen in his memory--the most vivid and intense feeling--come back from his starvation days when he had a wild rapture in pursuit of birds, rats, snakes that he had to kill with stones. Never, in all the years, had this rapture faded. Relic of his cruel boyhood days, when, like all boys, he had killed for the sake of killing, until some aspect of his bloody, quivering victim awakened conscience! Conscience then must be the great factor in human progress--the difference between savage and civilized man. Terribly strange for Adam to look at his brawny hands and remember what they had done to men! Over him, then, gushed the hot blood, over him quivered the muscular intensity, over him waved the fierce passion which, compared with that of his boyhood, was as the blaze of sun to a candle. He had killed men in ruthless justice, in strife of self-defense, but always afterward he had regretted. He had fought men in a terrible, furious joy, with eyes tingeing red, with nerves impervious to pain, with the salt taste of a fellow creature’s blood sweet on his snarling lips, but always afterward he was full of wonder and shame.