Most of the events from the past that are introduced into All the King's Men have a clear bearing either on the life of Willie Stark or on the life of Jack Burden. The story of Cass Mastern, however, seems to have little bearing on anything in the novel, even though it was to have been the topic of Jack's doctoral dissertation in history and even though it is the story of his supposed paternal grandmother's brother. Indeed, many readers have had difficulty with this episode, and some critics have argued that the presence of this episode in the novel constitutes a serious flaw.
Such arguments notwithstanding, the Cass Mastern episode is an integral part of the novel and serves several important purposes. This story stands as a clear indication of Jack Burden's inability to understand the past and as a measure of his lack of a moral base upon which to act. In addition, the story of Cass Mastern contains incidents that are parallel to other incidents in the lives of both Willie Stark and Jack Burden. The Cass Mastern story establishes the basic patterns of events that these other incidents follow; as these patterns are resolved in different ways, they play off against one another, and a fuller view of the complexity of human behavior emerges. In short, the Cass Mastern episode is directly involved in the thematic explorations of the novel.
Cass Mastern is one of three children of a poor backwoods couple. His older brother, Gilbert, left home early and became a wealthy plantation owner in Mississippi. After the elder Masterns die, Gilbert takes Cass and his sister Lavinia (Ellis Burden's mother) under his care. Lavinia is sent to a finishing school, and Cass is tutored and given responsibility for managing a small plantation, which he does very well. Then he is sent to Transylvania College in Lexington, Kentucky. There, introduced by Jefferson Davis, Cass Mastern becomes acquainted with Duncan Trice, who educates him in a variety of matters. He also introduces Cass to his wife, Annabelle. Nothing of importance seems to happen that first year, but during Cass' second year in Lexington, he begins an affair with Annabelle Trice. This affair lasts for a year and a half, until Duncan Trice learns of it and kills himself; his suicide appears to be an accident, but he makes sure that his wife knows that it is not, and later Annabelle Trice sells the slave who found her husband's wedding ring under the pillow. Cass Mastern takes upon himself the responsibility and the guilt for his friend's suicide, his mistress's reactions, and the sale of the slave, which separated her from her family. He tries to atone by finding the slave and setting her free, but he cannot trace her. He then runs the plantation, which Gilbert had given him, successfully enough to pay off his debts completely. When he has paid these debts, he frees his slaves and tries to run the plantation with hired labor. This is unsuccessful, so he goes to Jackson to study law. When the Civil War begins, Cass Mastern enlists as a private — although he could have been an officer — and, refusing to shoot another human being, he waits to die.
The first, and most directly relevant, function of this episode is to show Jack Burden's blind spots, his view of the world, and his detachment from other people and from events. After he has worked with these materials for a year and a half, Jack knows the facts very well. Not only has he got the facts from the papers at his fingertips, but he has gathered other information about the world in which Cass Mastern and his brother Gilbert lived. The problem that Jack has with writing his dissertation is not a lack of facts; in-deed, Jack is very good at ferreting out the facts, and he has done this in order to fill in the sequence of events in which Cass Mastern was involved. Instead, the problem is Jack's lack of understanding when it comes to human beings and human motivations: he cannot fully understand Cass Mastern. To an extent, he understands Cass' early life, plus the drinking, gaming, and whoring that Cass does when he arrives in Lexington, and he is able to understand the affair between Cass Mastern and Annabelle Trice, at least on the surface. But Jack cannot understand Cass' reactions and motivations after he learns that Duncan Trice's death was a suicide, rather than an accident. Jack cannot understand why Cass Mastern accepts the responsibility and the guilt for the affair, for his friend's death, for the sale of the slave girl, and, ultimately, for the institution of slavery. At this point in his life (he is a graduate student during the early 1920s, when he is, perhaps, twenty-two or twenty-three years old), Jack cannot accept the idea that one person's actions affect another person in any way, nor can he see why a person should accept responsibility for anything that happens. Thus the Cass Mastern episode reveals both what Jack is like and what he must learn in the course of the novel.
The affair that Cass Mastern has with Annabelle Trice, the wife of his best friend, parallels several other triangles in the novel. The most prominent of these is the affair between Monty Irwin and Jack's mother, who is married to Ellis Burden, Irwin's best friend. Like Duncan Trice, Burden dotes on his wife, and he is blind to his wife's affair for quite some time. Unlike Trice, however, Ellis Burden does not kill himself when he discovers what has happened. Instead, he leaves everything behind and turns to street-corner religion and to caring for his fellow man. In doing so, he combines several characteristics of both Duncan Trice and Cass Mastern: like Trice, Ellis Burden cannot accept and cannot face a situation; like Cass Mastern, he seems to accept the guilt and to turn to service to his fellow man as a means of atonement. Like Annabelle Trice and Cass Mastern, the guilty lovers (Jack's mother and Judge Irwin) do not marry and do not continue their affair. Obviously, Judge Irwin does not take the responsibility for his friend's departure, nor does he change the course of his life. On the other hand, he does not deny responsibility for his actions. As he does with the bribe and the death of Mortimer L. Littlepaugh, he seems to acknowledge that he has erred and has failed to live up to his own standards, but then he seemingly resolves that he will try to live the rest of his life more uprightly. Because of the other parallels, there is an implication that neither Judge Irwin nor Jack's mother planned this affair or even willed it; they were cast into close proximity and an affair developed because of passion.
The comparisons between these two triangles suggest the complexities of human motivation; they also suggest the complexities of trying to evaluate the actions of the participants. For example, is Judge Irwin more callous and less moral because he does not feel the intense guilt and need to atone that Cass Mastern feels — or is he simply more pragmatic and more accepting of the sinful side of human nature? Questions such as these become more complex still when other triangles in the novel are noted.
In a sense, Willie Stark, Anne Stanton, and Jack Burden are involved in a triangular relationship, although it is of a different kind. Jack and Anne, of course, are not married, but there is a special bond of longstanding between them. It is to Jack that Anne turns when there is some difficulty or when she needs someone to talk to; Jack has always considered her to be someone special, and he is totally numbed when he learns of her affair with Willie Stark. Indeed, toward Anne, Jack seems to feel the same kinds of feelings that Duncan Trice and Ellis Burden felt toward their wives, even though he is not married to her and even though he seems unaware of the strength of his feelings. In addition, Willie Stark and Jack Burden have approximately the same kind of relationship that Cass Mastern and Duncan Trice or Monty Irwin and Ellis Burden had: if Jack has a close friend, it is Willie Stark, and Willie Stark can talk with Jack in a way that he cannot talk with his other associates. Thus, the basic relationships in this triangle are similar to the other two triangles, but there are differences as well, and it is these differences that add to the complexity of the exploration of human motivations in this novel.
One difference between this relationship and the other two is that the affair between Willie Stark and Anne Stanton seems to have been undertaken quite deliberately. That is, it seems likely that Willie Stark suggested a liaison to Anne before she comes to Jack with the request that he find a way to convince Adam to accept the directorship for the hospital; she later indicates that it was only after she had learned about Judge Irwin's bribe and her father's protection of him that she had decided that there was no reason why she shouldn't become Willie's mistress. Another difference is that Willie Stark feels no qualms whatsoever about what he is doing; it seems probable that he is aware that Jack knows of the affair, but that does not seem to bother him. In addition, Anne admits the truth about her affair to Jack. Both of these differences, of course, can be attributed to the fact that Anne and Jack are not married and, indeed, have no steady relationship. A fourth difference lies in Jack's two-part reaction to the discovery that the woman whom he has idealized is now having an affair with another man. His initial reaction is to run from this information; his trip to California is similar to Duncan Trice's suicide and Ellis Burden's abandonment of his wife in this respect. However, Jack uses this trip to relive his relationship with Anne Stanton; although he attempts to attribute everything to "the Great Twitch," he admits to himself that he bears some responsibility for Anne's decision (apparently as Ellis Burden accepted some responsibility for his wife's infidelity). Furthermore, Jack returns to face the situation, rather than escape permanently; when the affair is ended by the assassin's bullet, Jack is there to provide whatever comfort he can, to try to pick up the pieces of his life, and to try and begin again.
After comparing the actions of the people involved in these triangles, each reader must decide which characters reacted most sensibly under the circumstances they were faced with. The novel itself does not make such judgments for the reader; instead, the variations of response are presented in order to show how different human reactions to similar situations can be. The fact that the Cass Mastern episode focuses so definitely on triangular relationships also provides a focus and a point of comparison for the other triangular relationships in the novel, providing the basis for the evaluation of the actions of the people involved.
There is one other triangular relationship that has a major impact on the novel but that varies significantly from the pattern established in the Cass Mastern episode. This is the Lucy Stark — Willie Stark — Sadie Burke triangle. There are some difficulties in comparing this triangle with the others. First, Willie Stark's sexual proclivities bring a number of other women into the equation. Nevertheless, Sadie Burke is Willie Stark's first, and primary, mistress, and she is the most enduring of his mistresses. In addition, Willie Stark returns to Sadie Burke after his other sexual flings, or at least he does so until near the end of the novel.
In this triangle, Sadie Burke plays the same role that Cass Mastern plays; Lucy Stark has approximately the same role as Duncan Trice; and Willie Stark plays approximately the same role as Annabelle Trice (that is, he is the erring spouse). There is no indication of when Sadie Burke becomes Willie Stark's mistress; it seems to be an established fact by the time Jack starts working for Willie. Furthermore, there is no indication of whether or not Lucy ever really learns about this affair; if she does, she gives no sign of it, although it may be one of the reasons that she moves out of the Governor's mansion. If she does know of Willie's many infidelities (there are indications that many people in the state know about them, so it would be hard for her not to know), she seems to accept them as being simply another of the aberrations that Willie has evidenced since he became governor. In this variation on the triangle, the erring spouse decides to return to the other spouse, an action that is not even contemplated in the other triangular relationships. In addition, it is the outsider — Sadie Burke — who becomes upset enough to take action. She certainly does not accept responsibility as Cass Mastern does, nor does she admit error and go on living as Judge Irwin does, nor does she forsake her lover as Willie forsakes Anne. Instead, she becomes angry at being thrown out — as though she were the wronged party in the affair — and takes the steps that lead to the assassination of Willie Stark. Even when Sadie is compared with the wronged persons in the other triangles — Duncan Trice, Ellis Burden, and Jack — her actions are directed toward the person who has done wrong to her (as she conceives it), rather than turning inward as the others do.
There are, then, at least four different variations on each of the basic positions in the triangle. What a person does in any particular position depends, of course, on the background of that person and on his or her personality. By presenting these four triangles, the novel enriches the reader's view of human nature. The question is not whether or not adultery is a proper thing; these episodes suggest that someone is always hurt in some way when adultery takes place. Instead, the question is how human beings react in the face of sin or wrongdoing — both their own and that of other people. The question is also how the wrongdoing affects the people involved, directly and indirectly. These, certainly, are major thematic concerns of the novel as a whole, concerns that are explored in other contexts as well. In this way, the Cass Mastern episode focuses attention on one kind of relationship between people, providing a point of comparison for other, similar incidents, and it is therefore tied into two of the major thematic concerns of the novel. The Cass Mastern episode is an integral part of All the King's Men, even though it does not seem so at first glance.