Critchley's Poem

In the opening paragraphs, the author defines humour as a disjunction between the way things are and the way they are represented in a joke. Critchley believes humour defeats our expectations by changing the situation in which we find ourselves.
Based on my understanding of the reading, expectation has a lot to do with jokes in the sense that it keeps us, the audience at the edge of our seats thinking or assuming one way and then suddenly turning that thinking or assumption around. As a result, we laugh at our failed expectations either by shock and surprise.

Tacit social contact is defined as an agreement about the social world in which we find ourselves as the implicit background to the joke. It is also an implicit shared understanding