John Steinbeck's The Grapes of Wrath portrays the different ways in which the central characters illustrate the various roles and responsibilities of the individual and society. During the course of the novel the Joads move from a concern only for themselves and their personal welfare to a concern for all the people of the world. Tom Joad moves from a strictly independent way of thinking only for his own comfort to a devotion to his family, and finally moves away from his family and accepts the world as his family. Ma Joad is shown to be the figure keeping the family together, and as the novel progresses she begins to become part of a larger human family. Lastly, Rose of Sharon is first only concerned about the welfare of herself and her unborn child and by the end of the novel her role is expanded and part of the struggle of mankind.
             Tom Joad appears to be the main protagonist and central character, and perhaps the one who develops most and survives in the novel. At the beginning of the novel, he is a sensitive, kind and communicative person. He can be referred to as being individualistic and quick to anger if he feels he is being pushed around. Tom focuses on his own personal and material well-being and of course, the welfare of the Joad family. After four years in prison, Tom is anxious to taste all the comforts of life. He tells Jim Casy he feels no guilt or shame about having killed a man and under the same circumstances he would do it again. He does not regret that the man is dead, but Tom feels he was only defending himself. The former preacher, Jim Casy, emphasizes that a human being, when acting alone, can have little effect on the world, and that one can achieve wholeness only by devoting oneself to one's fellow human beings. Jim Casy becomes his teacher, converting him by word and by his own example to the idea that a man cannot just look after himself but in the spirit of compassion is obligated to help others.
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