Fear can drive people to react irrationally, and in The Crucible, fear of witchcraft leads Salem down a path of hysteria, corruption, and revenge that nearly destroys the town. The townspeople are convinced that witchcraft is real and present in their town, despite the presence of logical explanations for the strange occurrences at the beginning of the play. Their willingness to embrace the rumors of witchcraft stems not only from their Puritan beliefs but also from the deep resentments and interpersonal conflicts that simmer within the town. While some, including John Proctor, Reverend Hale, and Giles Corey try—and fail—to quell the mounting hysteria, others cynically exploit the chaos for their own purposes. Parris uses the crisis to strengthen his authority as the town's religious leader, and Thomas Putnam gains revenge against Francis Nurse by having Rebecca Nurse accused of witchcraft.

Accused individuals who wish to live must confess—and in turn are expected to accuse others. This flawed system of justice thus not only falsely reinforces the legitimacy of the girls' claims but also perpetuates the cycle of accusations, enabling the trials to spiral out of control. The speed and ferocity of the witchcraft scare is precisely what makes the hysteria so difficult to halt, as doing so would require those in charge to admit that they have made grave errors in judgment. Indeed, Danforth admits as much when he refuses to postpone Rebecca Nurse's execution, citing his fear that "reprieve or pardon must cast doubt upon the guilt of them that died till now."