Fountain of Knowledge

The best definitions seem to revolve around a comparison with sci-fi and fantasy, which both share a "what if?" sensibility. In science fiction, things that are different than our world have a scientific explanation. In fantasy, things that are different than our world have a magical explanation. In bizarro, things that are different than our world have no explanation or need for it.

For example, in science fiction, people fly with jet-packs or spaceships or anti-gravity devices. In fantasy, people fly with broomsticks or spells or carpets or wings. In bizarro, people fly and there is no explanation or wonder at all.

Shared with both science fiction and fantasy is the idea of of a new reality, an internal logic, but absent is the idea that the new reality has to be even vaguely plausible or possible. Thus, a favorite bizarro theme seems to be different body parts acting independently, and often entirely disconnected from each other. No attempt is made to explain how that would work; none is necessary. Another favorite theme seems to be setting aside one or more rules of normal behavior, often with regards to sex or food. The important thing is that no notice or mention be made of the rules being set aside.