How do the events in this act affect readers perception of the situation in which proctor and the others find themselves?

We may say that it has to do with the change of subjects in the convrsation of the proctor family. E. g. John and Elizabeth talk about highly mundane subjects. The author also fills the athmosphere with guilt mirroring the same situation in a puritan society. Also the line between private and public and how it can be difficult to perceive. And another subject is the ambiguity of evidence. That makes the reader perception to be affected