A Fair Fight
The central conflict of On the Waterfront is the rampant corruption of the dockworker's union. Crooked and coercive violence is ubiquitous, and in the first five minutes of the film, a man is killed for almost speaking out against the corruption. If Johnny Friendly's racket is defined by an unfair fight, Terry Malloy's journey is defined by his search for a fair one. A former champion fighter, Terry was at his best in the boxing ring, fighting a man with his bare hands. His whole career went away and the glory of being a fighter was compromised when Johnny Friendly came into his life, bought a piece of him, and began using the boxing ring as an arena for placing bets. Terry had to give up the boxing ring, the locus of the fair fight, on the urging of his own brother, then got caught up in the corrupt racket of Johnny Friendly's mob. At the end, Terry finally confronts Johnny face to face and punches him, looking to start a fair fight. His desire to fight Johnny with his bare hands is again undermined by Johnny Friendly's corruption, as Johnny enlists the thuggish force of his mobster henchmen to knock the wind out of Terry. Terry eventually stands and walks to work, however, symbolizing the triumph of the honest man over the corrupt leader.
Conscience
Terry's psychic journey is a confused and conflicted one throughout. While he is part of Johnny Friendly's inner circle, which affords him a certain amount of protection, he wants to be able to speak out against what he sees as the corruption taking place at the docks. Finally, with the death of Joey Doyle, Terry is motivated to confront this injustice. Father Barry, longing to help clean the docks of corruption, encourages Terry to listen to his "conscience." Terry's conscience is another term for his connection to his own ethical thinking, his ability to fight for what is right. At first, Terry resists Father Barry's encouragement to listen to his conscience, shrugging it off and resenting the word. Eventually, however, he realizes that his conscience is the strongest asset he has, and that by doing the right thing he can save himself as well as all the dockworkers, so that they can secure the right to fair working conditions and a life without fear.
Corruption
In contrast to Terry's conscience and his desire for a "fair fight" is Johnny Friendly's endless corruption. The union has long been controlled by Johnny Friendly, who keeps most of the dock's earnings for himself and takes care of the select few in his inner circle, neglecting the needs of the common workers and threatening to murder anyone who speaks out against him. Johnny Friendly is the image of the corrupt dictator, one who keeps everything for himself and harms his own dependents. Corruption is pervasive on the waterfront. While Johnny and his men wear expensive clothes and diamond rings and do hardly any work, many honest dockworkers are denied work on a daily basis. The system is skewed to favor those who align themselves with the mob and with undermining justice, making corruption a major theme of the film.
"Deaf and Dumb"
In order to maintain order and strengthen the corruption of the docks, the union bosses must keep the dockworkers both quiet about what they see and as ignorant as possible of the system of corruption. In order to avoid punishment (or almost certain death), the dockworkers must remain "deaf and dumb," meaning they must not give up any information to the authorities or anyone who asks, even if they know that it's the right thing to do. For instance, when Joey Doyle is murdered, many of the dockworkers know what happened to him and why—indeed, he was murdered precisely for his refusal to remain "deaf and dumb"—but no one speaks out, for fear of being killed themselves. Enforcing a culture of silence and acceptance is how Johnny Friendly is able to keep control of his men, even if they know that what he is doing is immoral.
"People Living"
Edie Doyle is determined to discover who killed her brother Joey. After she walks home from the church with Terry, she tells her father that she doens't want to go back to her school where she is training to become a teacher. While Mr. Doyle and her mother wanted Edie to get an education so that she could be upwardly mobile and would not be trapped in the corrupt circumstances that have held them back, Edie is too angry about her brother's murder simply to go back to school and forget about it. She tells her father that she cannot continue to think about issues "that are just in books, that aren’t people living," as long as corruption is so powerful in Hoboken. Her desire to be where there are "people living" shows that she is committed to helping clean up the waterfront and make other people's lives better, not just her own. Hoboken, where there are "people living," contrasts with her school, where she will possibly be able to improve her situation, but won't be able to make any impactful change or learn who is responsible for the unjust killing of Joey.
Romance & Vulnerability
Though the film centers on the issues of corruption and crime surrounding the lives of the dockworkers, another major theme of the film is love. Edie and Terry are an unlikely pair, in that he is rough and uneducated and she is demure and ambitious. In spite of their differences (or perhaps because of them), they fall in love with each other, and reach a tender understanding. Each of them feels vulnerable in new ways with the other, and their bond is strong and galvanizing. Indeed, part of what motivates each of them to continue fighting to expose Johnny Friendly is their love and respect for one another. Edie's connection to Terry is partially responsible for her decision not to return to college, and Terry's decision to testify against Johnny is his knowledge that Johnny had Edie's brother killed. The film is dramatic and suspenseful at moments, but it is also defined by its central romance. Edie and Terry's courtship is charming and romantic, as they dance the night away in a dive bar, finding solace from their difficult lives in one another's embrace.
The Truth
Father Barry and Edie often implore Terry to listen to his own "conscience," but another important pillar of the advice they give him is a belief in a sturdy and immovable "truth." While the corrupt world of Johnny Friendly has rendered the definition of truth somewhat unstable, Father Barry and Edie insist that there is a truth that must be exposed, and that Terry is the man to do so. Terry is reluctant even to consider the meaning of the word truth. When Edie confronts him directly about what happened to her brother, he snaps at her, "Quit worrying about the truth all the time. Worry about yourself.” Then later, when Father Barry scolds Terry for holding up Johnny's bar at gunpoint, he insists that Terry's much more effective weapon is his grasp of the truth, saying, "You’ll fight him in the courtroom tomorrow with the truth, as you know the truth.” The truth is the strongest weapon in the film, stronger than Johnny's thugs and stronger than a pistol.