He had learned well the law of club and fang, and he never forewent an advantage or drew back from a foe he had started on the way to Death. He had lessoned from Spitz, and from the chief fighting dogs of the police and mail, and knew there was no middle course. He must master or be mastered; while to show mercy was a weakness. mercy did not exist in the primordial life. It was misunderstood for fear, and such misunderstandings made for death. Kill or be killed, eat or be eaten, was the law; and this mandate, down out of the depths of Time, he obeyed.
Jack LondonThus it was that in obedience to the law laid down by his mother, and in obedience to the law of that unknown and nameless thing, fear, he kept away from the mouth of the cave.
Jack LondonDon't loaf and invite inspiration; light out after it with a club, and if you don't get it you will nonetheless get something that looks remarkably like it.
Jack London