Hemingway employs both his plot and symbolism to further the theme of Doubt and Ambiguity. With only dialogue as the foundation for the plot, the discussion between Jig and the man is unclear and unresolved. In his minimalist style, Hemingway never mentions what the "it" is that the couple discuss as they converse. Jig tells the man that things are "like white elephants," suggesting that the baby she carries is symbolically a "white elephant" as are the distant hills.
Thus, the setting is the chief source of symbols. With the railroad tracks as symbolic of the divide between Jig who is romantic and optimistic and the nameless man who is practical and coldly objective, one side of the tracks has fertile land with vegetation while the other is barren. In the distance are the hills which symbolize the dissention between the couple. They possess something which is of no value anymore:
"Then what will we do afterwards?" [Jig asks]
"We'll be fine afterwards. Just like we were before."
"What makes you think so?"
In the end, the man says, "I'd better take the bags over to the other side of the station," indicating symbolically that he is becoming alienated from her.
One of the themes of "Hills Like White Elephants" has to do with making choices. The American seems sure about having Jig get an abortion while Jig is not convinced. However, Jig is also trying to decide how much she wants to remain in a relationship with the American and whether or not her decision to have the abortion is related to a decision to keep or give up the relationship. The irony of the situation is that the American continually tells Jig that he loves her and that things are going to work out fine even though his tone suggests that if Jig does not agree to have the abortion, then he will leave on the next train and never return. There is much ambiguity in the plot, and it is not even directly stated that the issue of debate is the abortion. This suggests that the theme revolves not around the topic of abortion specifically, but around the topic of making decisions. The abortion then is simply a symbol for the hard decisions that couples must make during the course of their relationships.