How does Zuckerman's book collection serve as a symbol of personal stagnation in the novel, Zuckerman Unbound?

Zuckerman makes repeated reference to his personal book collection, which at the time of the novel lies packed away in many boxes following Zuckerman's move to his new apartment. One symptom of Zuckerman's personal and artistic stagnation during the narrative is his inability to unbox his books or get any type of reading or writing done.