Which universal theme does the author incorporate in this passage? "'Answers to the name of Buck,'" the man soliloquized, quoting from the saloon-keeper's letter which had announced the consignment of the crate and contents. "Well, Buck, my boy," he went on in a genial voice, "we've had our little ruction, and the best thing we can do is to let it go at that. You've learned your place, and I know mine. Be a good dog and all 'll go well and the goose hang high. Be a bad dog, and I'll whale the stuffin' outa you. Understand?" from The Call of the Wild by Jack London the illusion of progress