The narrator and "Shiny" are foils. They have similar upbringings (they graduate from the same school in Connecticut), but "Shiny" is unmistakably Black, whereas the narrator can pass for white. Ultimately, they both end up reasonably wealthy and successful. Still, their lives look different because of the choices available to each of them. "Shiny," who was always the best student in the school, becomes a prominent professor who fights publicly for racial justice. He deals with overt racism, but he is unapologetic about who he is. He has made good on his promise, in his graduation speech, to strive for a more just world.
The narrator's light skin, meanwhile, allowed him to blend in for a time with the white children while at school. He is, in fact, the one who gave "Shiny" his schoolyard nickname (which is rather racist) as a way of bonding with his classmates. Later in life, the narrator has again capitalized on his proximity to whiteness in order to get ahead. But running into "Shiny" as an adult makes the narrator question just how far ahead he has gotten. "Shiny" is the kind of man the narrator confesses that he sometimes wishes he had become: his successes are visible evidence of Black people's upward mobility, whereas the narrator looks outwardly like a moderately successful white man.
The fact that "Shiny" does not out the narrator to his girlfriend when he realizes that he has been "passing" highlights some of the complicated politics of "passing." Even if "Shiny" does not enjoy the privilege of light skin, he is in some ways in a more secure position than the narrator because he doesn't have anything to lose. Were "Shiny" to tell others that the narrator is Black, the narrator might even be at risk of physical violence at the hands of the closest people in his life. By placing these two characters side by side, Johnson upends the idea that "passing" would be a desirable outcome even if it were possible for all Black people.
It is possible to read the narrator and the millionaire as foils. This becomes especially clear when they part ways in Chapter 9:
He gave me a check for $500, told me to write to him care of his Paris bankers if I ever needed his help, wished me good luck, and bade me good-by. All this he did almost coldly; and I often wondered whether he was in a hurry to get rid of what he considered a fool, or whether he was striving to hide deeper feelings of sorrow.
The millionaire and the narrator both find racial politics abroad much more tolerable than they find them in the United States, even though they both have an appreciation for ragtime—a quintessentially American art form. Traveling with the millionaire has been a respite for the narrator. It has allowed him to see the world and gain recognition as a musician. But he nonetheless feels compelled to go back to the United States, where his music will come face to face with thorny racial politics. The millionaire has argued that there is nothing to be gained if the narrator returns home. The life the millionaire lives out (which seems to involve a long stretch of carefree travel until he dies by suicide) represents the life the narrator may have had if he had stayed abroad. The mix of freedom and tragedy in this alternate life is emblematic of the narrator's deep ambivalence about his own choices.
This divergence of the two characters' politics and choices is enough to make them foils, but this passage suggests something more as well. It illuminates that traveling with the narrator has perhaps been more meaningful to the millionaire than he previously let on. Like the narrator, the millionaire maintains an inscrutable mask even with his closest friends. The fact that the narrator can't tell whether the millionaire is hiding "deeper feelings of sorrow" raises the question of what else he is hiding. The narrator never voices the question, but there is a real possibility that the millionaire could have been a Black man passing for white before the narrator ever chose to do the same. If so, the millionaire's ultimate death by suicide suggests a grim outlook for "ex-colored men" who have, as the narrator writes at the end of the novel "sold [their] birthright" of Black identity "for a mess of pottage." What's more, the idea that the narrator could be fooled by someone else's decision to pass would make racial categories appear all the more absurd.
