The downy pillow covered his ears but did not mask the sound. Sleep eluded him for hours, and he heard it still: a persistent scraping in the corner of his room. Sitting upright at last, he peered into the darkness. It was as he'd suspected. His uncle's trunk, an old army footlocker, was the source of the sound. Fine then, he could resolve this mystery. He swung his legs to the floor with conviction. How does the excerpt exemplify the ideas Stephen King describes in "Danse Macabre"?