Just about every sentence we say or hear is a recombination of existing words appearing in that exact configuration for the very first time.

Puns often seem to propagate in direct proportion to efforts aimed at suppressing them. Tell someone they can't say something, and they'll find another way, much as a river will eventually find a way round any mountain on its journey to the sea.

Not to pun at all would be more challenging than most people might imagine.

Puns are at their core defined by multiplicity of meaning, not necessarily humor. The common expectation that puns should always be funny, or die in the attempt, is a relatively modern development.