Mary Warren is a great character when it comes to character development. The Mary Warren in Act 1 is not the Mary Warren of Act 2. She starts out as a shy and diminutive little girl-- a complete opposite to Abigail Williams-- who took over the domestic position in the Proctor household. But the importance of her role as victim in the Witchcraft Trials has given her a confidence that she did not previously have. When she enters the Proctor home in Act 2, she explains in great detail what valuable testimony she has been able to give and how it is leading to one woman's jail time and another woman's hanging. She is just as swept away by the intensity of the proceedings as the judges, and truly believes that all her afflictions are the result of witchcraft over her body by the women who stand accused. In other words, she buys into her own hype. This little girl, who had no power, no voice, is suddenly in the spotlight and believed without contradiction.