How does mass hysteria prey on weak people?

In The Crucible, hysterical fear becomes an unconscious means of expressing the resentment and anger suppressed by strict Puritan society. Some citizens of Salem use the charge of witchcraft willfully and for personal gain, but most are genuinely overcome by the town’s collective hysteria: they believe the devil is attacking Salem. And if the devil is attacking your town, then ensuring that your neighbor is punished for selling you a sick pig suddenly becomes a religious necessity, a righteous act that protects the God you love and proves that you’re not a witch or a devil-worshipper. The Crucible shows how religious fervor fuels hysteria and leads to conditions that sacrifice justice and reason.