What is the significance of Oskar only wearing white but all the while looking for "Black"?White and Black are on two opposite sides of the spectrum, a spectrum which also mirrors Oskar's journey of self discovery (or any journey in general). He starts his search in a state of confusion, still clueless about many aspects of his father's death/life, and ends it with emotional closure.
One might think of black as being empty and white its opposite, but thinking in terms of a blank slate, or a sheet of computer paper, the reverse can be just as plausible. Perhaps Foer is trying to "fill in" Oskar's blank clothing with his search for "Black." Oskar's choice of clothing may signify his emptiness, and longing for answers. Just as his grandfather chooses actual writing to fill in blanks, Oskar is searching for the equivalent. Why not express that through a bizarre choice of everyday attire?
