At the beginning of section II, what does the narrator say Dexter wants in "Winter Dreams"?
The narrator says, "the quality and the seasonability of these winter dreams varied, but the stuff of them remained."
The word "seasonability" can be troublesome for readers. It is an archaic word that means occurring at the appropriate time—like the word "opportune." Perhaps Fitzgerald meant that the different practical permutations of Dexter's dreams were not fixed, but they were consistent in their essence.
The narrator puts a finer point on what this opening sentence means when he goes on to carefully separate what Dexter does not want—to associate with rich people and the things, tangible and intangible, that they possess. Dexter wants "the glittering things themselves." He aspires to have what the rich have without conscious thoughts about why he wants it. His quick success after college is the first step, he believes, in surpassing what rich men his age have. He does not seek approval from his social superiors—he wants to out-earn them on his own terms. He notes the flaws in people above him in social standing, and his own rise builds his confidence. Dexter seeks self-reinvention and longs to break from his past and leave no trace of who he used to be; that is the "stuff of them" with regard to his winter dreams. How he makes his fortune, a string of laundries or any other industry, is unimportant. For Dexter, the destination is all and the journey is incidental.
At the beginning of Part II of Fitzgerald's "Winter Dreams," the narrator comments that while the quality and the occasion of Dexter's dreams alters, the substance of these dreams--"the stuff of them"--remains the same. That is, Dexter yearns for that elusive quality of the rich which makes them desirable.
At one time F. Scott Fitzgerald grumbled to Ernest Hemingway, "The rich are different from you and me." Despite Hemingway's cryptic response, "Yes, they have more money," Fitzgerald was never convinced that the rich did not hold some magical quality. It is this very magic of which Dexter dreams. Like Fitzgerald himself, he is convinced that the wealthy are somehow superior beings. Consequently, he pursues an education at an "older and more famous" university in the East, rather than the state university to which his father would have paid the costs, because he hopes that at a prestigious school in the East he can associate with the wealthy. Perhaps then he, too, can attain "the glittering things." Clearly, this attainment of the "glittering things" is what composes Dexter's winter dreams.