Mayor of Casterbridge is a tragedy of the most moving type. It fulfills the Aristotelian requirement of the depiction of the downfall and death of the hero because of some tragic flaw in his character. It also conforms to the pattern of the Greek classical tragedy in the cruel workings of Fate. Chance or Coincidence also has a significant part to play in this novel. The tragic content in the novel assumes a cosmic significance. Moreover, the tragedy in it is caused not only by mere external factors or circumstances, but also by the conflicts and tensions going on in the mind of the hero, as well as a tragic flaw in his character.
In The Mayor of Casterbridge, Hardy use of coincidence implies that he shares Aristotle's belief that the plot is important in the creation of a tragedy. In much the same way as Aristotle, Hardy attaches special importance to the three elements of the plot in a tragedy: the reversal, the recognition, and the final suffering. This basic structure of the plot in the novel with its emphasis upon the single protagonist and upon the course of the hero's downfall is patently Aristotelian. Hardy follows the rise and fall of Michael Henchard, a poor agricultural worker who gains both fortune and respect upon becoming the mayor of Casterbridge. Unfortunately, the consequences of his past transgressions contribute to the tragic decline in Henchard's material, social and familial welfare.
In Hardy's novel, Mrs Goodenough, the furmity woman from the opening chapter, enacts a function similar to that of the Corinthian Messenger in Oedipus the King. The return of the furmity woman and her dramatic revelation in court plays a vital role in hastening Henchard's decline. Mrs. Goodenough exposes Henchard's shameful secret: the sale of his wife Susan and their child, Elizabeth-Jane, to a sailor for five guineas two decades earlier. Her declaration results in Henchard's social and financial ruin, as the amends he had made in after life were lost sight of in the dramatic glare of the original act.
According to Aristotle, a tragedy must contain the presence of a tragic hero: "a leader in his society who mistakenly brings about his own downfall because of some error in a judgement or innate flaw". Early in the novel, Henchard is at the height of his prosperity and resides at the top of fortune's wheel. He is well liked and highly esteemed by the townspeople of Casterbridge. Consequently, Henchard position in society is high enough for his fall to be considered tragic. Henchard's attributes such as his pride, his impulsive nature and his ambition are exactly the conditions that cause his downfall and his destruction. His character traits and his subsequent reaction to certain circumstances lead to his financial ruin, and to the destruction of his relationships with the others about whom he cares most.
In The Mayor of Casterbridge, Hardy unites Michael Henchard's tragic fall with his excessive pride, his impulsive nature and his ambition to succeed. Throughout the novel, Henchard makes many mistakes: he fails to maintain his wealth, his social position and his relationships with those who care for him. His jealousy of Farfrae causes him to lose both a faithful employee and a good friend. He feels threatened by Farfrae's sudden success; thus, he dismisses Farfrae. Donald Farfrae's dismissal leads to a drawn-out business competition between the two corn-factors that strips Henchard of his personal possessions, his public favour as mayor, and the two women in his life: Lucetta Templeman and Elizabeth-Jane Newson.
In an Aristotelian tragedy, the most important element in the audience's response, catharsis, depends upon the emotional effect of the literary work. Despite being classified as a novel, Thomas Hardy's The Mayor of Casterbridge evokes both the feeling of pity and fear in response to Michael Henchard's suffering. Hardy creates the most valid and meaningful modern revival and adaptation of an Aristotelian tragedy. Hardy combines the elements of plot and the presence of a tragic hero to induce a cathartic experience at the end of the novel.