In life today, guilt by association often is indeed guilt. If you gave answers to someone sitting next to you, you are just as much at fault for cheating as your peer. If you are watching that occur between two others and don't tell, you are guilty for not letting the teacher know. That's not comfortable but it is true. If you are in a car of your own will knowing that a friend has a gun, you will be guilty by association if your friend is ready to use it on another human being. Now, if you had no idea, you can claim that and work to prove it.
In Salem's witchcraft hay day, this wasn't guilt by association. This was a complete defense of one's friends who were known innocents. This was standing up for rights, and what was right. Some sense of something very wrong happened among the people, and the hysteria produced such a dramatic effect that it is reason for us to stop and consider some of our own accusations sometimes. You know the root had to do with children. Do children ever lie? Of course! The problem is that they do not understand the power of the consequences their lies may carry. Furthermore, the adults who perpetuated the hangings and accusations had land and prominence to gain. Look at the Putnams.
There are several examples of "guilt by association" in Act Three of The Crucible. The first comes when Proctor and his friends present a petition to the courts, where close to one hundred townspeople signed their names, asserting that the arrested women were not witches, but instead righteous, god-fearing people. The courts, instead of being impressed that so many people were willing to testify to the good nature of the accused, instead assume that they must also be guilty and covering for the witches. They think it is some sort of scheme to get the guilty women out of jail and back causing havoc in the town. So, they arrest all of the people that signed the petition.
The second example is the unnamed witness that declares he heard Thomas Putnam say that he had prompted his daughter to accuse a man of being a witch, simply so that he could buy up that man's land. Instead of believing the witness's testimony, they assume that the man is lying, and that he too should be questioned. To top it all off, Giles Corey, who presents the information, is arrested too, merely for relaying the information.
So, those are a couple blatant examples from Act Two where innocents are assumed guilty simply because they associate and defend the women and men who have been arrested. It is pretty sad. In these cases, none of the accusations of guilt were valid or true. Now, if Giles Corey had been at the same party where a bunch of witches had been performing spells, then maybe the entire "guilt by association" theory would hold some credit, but in this case, there was no proof or logical attachment to the actual guilty parties.
That can help to get you started; good luck!
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