In Hemingway's A Farewell To Arms the idea of existentialism is often thrown around. Existentialism basically operates under the belief that there is no inherent meaning in life, but that one must create their own individual meaning for their own life. In the novel, Lieutenant Henry falls in love with the lovely Catherine Barkley, and as the war progresses, Henry often uses thoughts of Catherine to motivate him to continue.
During the retreat from Caporetto—one of Hemingway's most famous pieces of writing—Henry fantasizes about Catherine in bed with him. He fears to lose her and never seeing her again. In this sense, the only meaning he finds throughout the brutal war is love.
Toward the end of the novel, when Catherine is pregnant with Henry's baby, the novel reads:
"When there was a good day we had a splendid time and we never had a bad time. We knew the baby was very close now and it gave us both a feeling as though something were hurrying us and we could not lose any time together." (311)
Their lives only find meaning in each other. By enjoying their time, they are able to appreciate life, but as the baby's due date approaches, a general sense of dread fills Henry's heart. Perhaps he senses the danger that awaits them, for Catherine and the baby both die, but it's even more likely that Henry is having an existential crisis. He fears to lose the life he has with Catherine in lieu of parenthood. There is no meaning to his life besides what he assigns it, and his meandering days with Catherine are all that he cares for.
One of the more clearly existential passages in A Farewell to Arms is this:
"I was always embarrassed by the words sacred, glorious, and sacrifice. . . . We had heard them . . . had read them, on proclamations . . . and I had seen nothing sacred, and the things that were glorious had no glory. . . . Abstract words such as glory, honor, courage . . . were obscene beside the concrete names of villages, the numbers of roads, the names of rivers, the numbers of regiments and the dates."
One of the major existential ideas is that personal experience matters more than what society or religion tells you. The words "sacred," "glorious," and "sacrifice" are clearly religious words: the glory of the Crusades, the sacrifice of Jesus, etc. Words like "honor" and "courage" were used by politicians to justify the war, to provide some sort of patriotic dogma for continuing to participate in it. For Henry, these abstract words, which reflect the political and social agendas of those in charge of the war, are not only meaningless but completely absurd to his own experience, which is of war as the total opposite of what it should be.
In contrast to these abstract words, which reflect the ideals of politicians trying to draft people into the war, or religious people trying to justify why it is occurring, the words of "concrete" items like "villages, the numbers of roads . . ." hold much more meaning for Frederic. This is because unlike the abstract words, the concrete words are relevant to Frederic's self. They have meaning for him and thus are more real and genuine, in keeping with existentialism's philosophy of the importance of the self in making meaning. In existentialism, one's self-made meaning is seen as much more philosophically valid than societally created meaning and dogmas.
In A Farewell to Arms, scenes that explore individualism and/or an exploration of identity are good places to examine the role that existentialism plays in the novel. In short, existentialism revolves around the idea that each individual must create his/her own self and that there is no "essence" to what makes up a person. At the beginning of the novel, the protagonist Lt. Henry is left unnamed, which is an implicit reference to the existentialist idea that Lt. Henry must "create" himself. Before Lt. Henry meets Catherine Barkley, he has little sense of individual purpose. However, as their relationship progresses, Lt. Henry builds his life around Catherine. When the priest visits Lt. Henry in the hospital, Lt. Henry, although sympathetic to the priest's ideas about God, cannot bring himself to say that he believes in God, but he does believe in the relationship that he has with Catherine. Thus, he "creates" himself around the love that the two share.