Silence has meaning. It is not merely the absence of speech. It is in fact a form of speech. It means different things in different contexts. In one context, such as that described by Covino from Jane Austen's Persuasion, it shows that the listener agrees with the speaker. Her silence is agreement. In other cases, silence might mean anger, disagreement, fear, or some other emotion. We can tell what the silence means by the situation in which the silence takes place.
The meaning of a moment of silence might be changed if the situation were different. Covino says that Wentworth's behavior toward Louisa and her silence show the nature of the power relationship between the two. Wentworth is like the teacher and she is like the pupil. Wentworth is complimenting the woman, and she agrees with her silence. If Wentworth threatened her, her silence might mean something else, such as fear or anger. If Wentworth insulted Louisa, her silence might mean disagreement and anger. Silence communicates meaning, but the meaning will depend on the situation in which the silence takes place. It is impossible just to say that silence means agreement, because sometimes it does and sometimes it does not. We have to ask what was taking place when the silence occurred and how the two people involved are related to one another and how they act toward one another. We can then decide what a given case of silence is intended to mean.
Richard Weaver suggests that there are certain terms which will meet with approval from any audience. He wrote this in 1955 and provided a list of words. He was writing in a society that had a stronger center than we do today. That society had core beliefs which could be brought out of an audience when certain terms were used. This was because everyone agreed about the meaning of those terms and also agreed about the value of those meanings. Society today is more divi