Once you've dissected a joke, you're about where you are when you've dissected a frog. It's dead.

Banquets of the Black Widowers (1984), p. 49; comparable to "Humor can be dissected, as a frog can, but the thing dies in the process and the innards are discouraging to any but the pure scientific mind." — E. B. White, in "Some Remarks on Humor," preface to A Subtreasury of American Humor (1941)