The American dream in the book refers to the dream of wealth. Gatsby's
desire to get into the upper class and wealth and money actually
corresponds to the "gold rush" that once swept the United States.
When the American dream is reduced to a pursuit of money and social
status without considering how to enrich the spiritual world and lead a
meaningful life after having wealth, the American dream is a kind of
short-sighted, illusory dream without continuity and vitality.