While there is a list of people in The Crucible responsible for the hysteria that grips Salem, a more interesting culprit might be the town's culture.
Abigail, the girls, Hathorne and Danforth, Reverend Parris, and the Putnams all help to cause the hysteria in Salem. We could even make a case that Hale played a role in encouraging the Salem hysteria. However, Miller makes a point that Salem's culture was predisposed to the hysteria that is the basis for The Crucible.
Much of the analysis about Salem's culture comes from the Act I stage directions. Miller's details help us gain insight into Salem. Miller talks about the town's intense seriousness towards daily life. They had "no novelists- and would not have permitted anyone to read a novel if one were handy." There was no theatre or anything "resembling 'vain enjoyment." Dancing and celebration were seen as work of "jokers" and not encouraged. The town's extreme seriousness showed a lack of perspective. It is why panic grips the adults when they find out that the girls were in the woods. For example, Parris is aghast when he asks Abigail if the girls were dancing. When Rebecca Nurse dismisses what happened in the woods as childish immaturity, she is dismissed. Her common sense approach is no match for the intense seriousness that is a part of Salem life.
People who broke the seriousness to which Salem committed itself were dealt with severely. Miller talks about the town's "practice of appointing a two-man patrol whose duty was to 'walk forth in the time of God’s worship to take notice of such as either lye about the meeting house, without attending to the word and ordinances, or that lye at home or in the fields with-out giving good account thereof, and to take the names of such persons, and to present them to the magistrates, whereby they may be accordingly proceeded against.” Reporting on people's behaviors and "naming names" were embedded in Salem culture. Miller includes this detail because he sees it as a major contributing factor to the hysteria surrounding the witch trials. Salem people were not able to simply let people live their own lives. Rather, there was a constant intrusiveness that defined Salem culture: "This predilection for minding other people’s business was time-honored among the people of Salem, and it undoubtedly created many of the suspicions which were to feed the coming madness." The need to constantly report on other people who were "breaking the rules" was a cultural spark that flared into a wildfire.
Finally, Miller feels Salem people had a fear of "the other" that contributed to the hysteria. Miller argues that Salem did not deal well with anything seen as different. For example, they saw the forest as "the last place on earth that was not paying homage to God." Darkness and anything that was not fully understood was seen as bad. What they did not understand was demonized as the work of "the Devil." Miller points out that their fear of "the other" was based on insecurity about their town's purity. They "found it necessary to deny any other sect its freedom; lest their New Jerusalem be deviled and corrupted by wrong ways and deceitful ideas." The result was "an air of innate resistance" where persecution became a part of their cultural residue: "They believed, in short, that they held in their steady hands the candle that would light the world." This candle lit the fires of hysteria.
Several characters in The Crucible play an active role in spreading hysteria. However, there is much to be said about how the culture of Salem might have had a role in encouraging its emotional contagion and madness.