The concept of denial in Arthur Miller's play The Crucible is crucial to the hysteria which breaks out in Salem. Many of the characters deny something at one point or another in the play.
Abigail Williams denies many different things throughout the play. In the beginning, she denies having anything to do with Betty's "illness." When questioned about her being put out of the Proctor house, she denies any wrongdoing (even though she was fired by Elizabeth Proctor for having an affair with John Proctor). Later, Abigail denies being apart of witchcraft only to resend her denial when it seems to benefit her.
John Proctor, while coming clean to Elizabeth, initially denies the admittance of the affair publicly. He knows that it will blacken his name.
Elizabeth Proctor denies, in court, that he husband was a lecher. Unfortunately, John had already told the court the truth and her denial only ends up causing more problems for her husband.
Many of the citizens accused of witchcraft deny the accusations. It is not until they are threatened with their lives that they admit, falsely, that they are witches.
The courts also are in denial. They fail to consider the fact that the whole town has been played for fools. The courts deny any relevant evidence, putting all their trust in spectral evidence (which later is thrown out because an accusation is made against Hale's wife).