What does the wall symbolize?
As walls are commonly thought to be, it is an obstacle, or a stopping point. In the case of Juan Mirbal and Tom Steinbock, it is the place where their lives will end. They are executed by the falangistas while they are propped in front of the wall. It is both a literal and a metaphorical wall that Tom and Juan have come up against; their protestations are futile, and they are brutally shot to death.
The wall can also be interpreted as symbolizing the line between life and death. When a man is on one side of the wall, he is alive. Once on the other side of the wall, he has ceased to live. Sartre and other existentialist writers and philosophers thought of humankind's situation as the duality of "being" and "nothingness." Because Pablo Ibbieta is thought to have aided the falangistas in their desire to locate Ramon Gris, his existence is preserved. The absurdity of his survival is not lost on Pablo; he laughs because he had tried to protect Ramon Gris by giving the falangistas misinformation about his whereabouts; instead, he sent them directly to Gris. The relationships of events in the story are binary—life/death, truth/deception and being/nothingness—just as there are two sides to the wall.
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