According to Aristotle, a tragedy is an imitation an action according to the law of probability and necessity. It is rooted in the fundamental order of the universe. Therefore, it arouses not only pity but also fear as the audience can envision themselves within the Cause- and- effect chain that is created.
Murder in the cathedral written by T.S.Eliot, is a ritualistic poetic drama, where the writer is given the opportunity to consider the inner thoughts and doubts of the central character. T.S. Eliot has used elements of the Greek Tragedy in this particular play for example the Greek chorus, which comments and responds to the unfolding drama. In Murder in the Cathedral the chorus comprises of women of Canterbury. The Greek chorus is an iconic element in the play.
The first feature of a tragedy according to Aristotle is the 'Plot'. Aristotle further provides the structure of a plot itself. The first component of the plot is the 'Exposition'. In the play Murder in the Cathedral the exposition will probably be the beginning of the play when the women of Canterbury and the other commoners gather at the Archbishop's Hall to discuss the return of Thomas Becket. Here they also introduce the conflict that had taken place in the past between Henry II and Thomas Becket because of which he was exiled or fled to France. Second is the Rising action, the rising action in this play would be the entrance of Thomas Becket and the tempers. One by one as Becket declines the suggestions of each temper it indicates the rising action. Third, is the climax, the climax arrives when the fourth and last temper arrives and suggests that Thomas make himself a martyr. As in doing so he will be remembered as eternally powerful. The tragic flaw or 'Hamartia' is recognized soon after this as Thomas admits to considering martyrdom in his private time. He does not want to be hated by all but be remembered eternally. He struggles with pride. This is followed by the falling action, which is probably his death. And at last the play ends with the denouement when the chorus claims that living up to the sacrifice of Thomas Becket is very difficult however taking up the challenge will make them spiritually richer.
The plot therefore is structurally self contained as Aristotle demands, except for the beginning. T.S.Eliot wrote the play assuming that his audience would be aware of the conflict that had taken place between King Henry II and Archbishop Thomas Becket. The incidents however are bound together by internal necessity, each action leading inevitably to the next with no outside intervention.
The plot of Murder in the Cathedral resembles a complex plot, which includes both 'reversal of intention' or 'peripeteia' as well as 'recognition connected to the catastrophe' or 'anagnorisis'. Here the reversal of intention takes place at the end of part I and in the interlude where Becket does not succumb to the temptation offered by the tempers and making himself a martyr for the wrong reasons and decides that he will "no longer act or suffer," and will instead face `his martyrdom not as something he wants, but as something he is willing to accept. He has accepted his fate.
Therefore in all these ways we see that Murder in the Cathedral by T.S.Eliot follows Aristotle's plot structure therefore enabling us to analyze it as such.