Since bad art has a harmful effect on society, it should never go unchallenged; but since the bad artist (like the good one) is an artist at all only because he claims he is, and has gotten at least one other person to believe him, how is he to be challenged? The only available rules are those of the gunfighter.

Artists have been shooting at artists for centuries. It’s a healthy sport if managed with a measure of civility, gun against gun, nothing personal or mean. Being forced to articulate and defend a position can make a bad artist better—people are more educable than we generally admit—and a stupid defense, though not always proof that the art is fraudulent, can alert people to the strong possibility that the artist is a fool, or emotionally cracked, or a philistine in cunning disguise. […] My object here is therefore not to start up such gunfighting, or even to encourage it, but to make it a little more orderly, a little more deadly.

John Gardner, On Moral Fiction (1978)