The existential belief is shown strongly throughout both books. The main character from "The Plague," Dr Rieux was, maybe even without realising it, was an existentialist. "The plague affected everyone, no one was safe." Had there been a God, he would have been selective. For instance, in the Bible when Moses wanted to lead his people away, God selected who to kill on the basis of their not having some blood on their door. The plague made no such selection. It killed every kind of person. In "Iron in the Soul," exactly the same thing happened. The plague of war made no selection. In fact, the only way that a selection could be made was by people themselves. Thus we see that if man kind has the power to choose who to kill; who to be the victim, he must have God within him.
Taking another look at both books we see that man's ability to save lives is more powerful then his ability to kill. A beautiful scene is described in "Iron in the Soul," when Daniel spotted a child who was about to commit suicide. He secretly followed him and was suddenly faced with a decision; watch as the boy brings about his own demise or allow himself to be noticed, with the knowledge that the boy, realizing that he was being watched, would not commit the act. "So long as I am here, you are quite incapable of killing yourself." Is this power over life and death not proof enough of a God-like being inside Daniel and, indeed, all people?.
In contrast to Daniel, Cottard from "The Plague," was the most evil of all the main characters. He not only committed a major crime, but also appeared quite cheerful when the plague came along, killing everyone around him. Suddenly everyone was in the same miserable state as he was and he thrived on their suffering. Yet he still lived on to the end. On the other hand, a child of pure innocence and integrity, who should have survived had there been a god, died a horrible death. The innocent also die in "Iron in the Soul," when, for instance, the printer was shot trying to escape from the train.