There’s a whole class of jokes that seem to have no setup what so ever. These jokes have setups, but they are not part of the performance. The setups for this style of jokes are built from existing information in the form of shared knowledge. This means the majority of the joke, which includes the setup, target assumption, and connector are things we already know about.
Some of the shared knowledge styles of comedy are satire, parody, TV topical monologues, information in the immediate environment, comments on current statements, and more. All of these styles rely upon people knowing the idea being made fun of. You must have something to satirize to do satire. Hence, there is no need for a performed setup because the target assumption and connector already resides in the minds of the audience.
As a comedian or comedy writer, the distinction between a one-liner joke which has a setup and jokes without performed setups is essential. This allows you to identify the mechanisms even when the majority of the joke structure exists as shared knowledge. If you’re not looking for it, it can seem invisible.
Let me illustrate this with something that actually happened to me. I was sitting in a Chinese restaurant in China Town. It was a very authentic establishment, and some of the other patrons were Asian immigrants – some spoke little or no English. They had a TV up in the corner of the room showing a Gallagher concert starting.
Gallagher made his entrance riding a bicycle with a square back wheel, and everybody watching cracked up laughing. Regardless of language or cultural differences, everyone knows the basic form of a bicycle.
This joke has no performed setup because everyone already knows how bicycles work, which includes the target assumption that a bicycle’s wheels are round. To make a joke, all he had to do was think up a reinterpretation of using a square wheel, and then present it as the punch, (Gallagher rides a bicycle with a square back wheel), to get the laugh.
Seeing the bicycle with a square wheel caused the audience to reevaluate the target assumption that a bicycle’s wheels are round and it shattered that assumption. No matter how silly, a bicycle can have a square wheel. When you shatter an audience’s assumption, they laugh.
On a daily basis, everyone makes tens of thousands of assumptions without realizing it. It’s these unconscious assumptions that are the basis for jokes without performed setups. Whenever anyone assumes anything, you have an opportunity to make a joke. To write a joke without a performed setup you must learn to recognize already accepted assumptions.