Salem Witch Hunt Example of Power of Evil

Between 1692 and 1693, more than 200 people in colonial-era Salem, Massachusetts were falsely accused of practicing witchcraft, and 19 of them were executed. More than three centuries later, the Salem witch trials remain one of the most disturbing, traumatic moments in American history, and an example of the perplexingly enigmatic nature of evil.
Why, in a paroxysm of paranoia, did Salem's citizens turn on their own neighbors, and fantasize that they had become minions of Satan and committed crimes that never occurred? Why was Salem's populace so willing to believe the worst, and why did people acquiesce to colonial officials' use of breathtakingly cruel methods of torture—such as crushing an elderly man's ribs under the weight of rocks--to extract confessions from the accused?