The range of Mark Twain's humour, from the ludicrous anecdote with comically mixed morals to the profound parable with grimly ironic conclusion, takes the measure of the ethical nature of the man. It can best be illustrated, I think, by a comparison of his anecdote of the theft of the green water-melon and the classic fable of 'The Man that Corrupted Hadleyburg'. Mark stole a water-melon out of a farmer's wagon, while he wasn't looking. Of course stole was too harsh a term --he withdrew, he retired that water-melon. After getting safely away to a secluded spot, he broke the water-melon open--only to find that it was green, the greenest water-melon of the year.
The moment he saw that the water-melon was green, he felt sorry. He began to reflect--for reflection is the beginning of reform. It is only by reflecting on some crime you have committed, that you are “vaccinated” against committing it again.
So Mark began to reflect. And his reflections were of this nature: What ought a boy to do who has stolen a green water-melon? What would George Washington, who never told a lie, have done? He decided that the only real, right thing for any boy to do, who has stolen a water-melon of that class, is to make restitution. It is his duty to restore it to its rightful owner. So rising up, spiritually strengthened and refreshed by his noble resolution, Mark restored the water--melon--what there was left of it--to the farmer and--made the farmer give him a ripe one in its place! Thus he clinched the “moral” of this story, so quaint and so ingenious; and concluded that only in some such way as this could one be fortified against further commission of crime. Only thus could one become morally perfect!
Here, as in countless other places, Mark Twain throws over his ethical suggestion--a suggestion, by contrast, of the very converse of his literal words--the veil of paradox and exaggeration, of incongruity, fantasy, light irony. Yet beneath this outer covering of art there is a serious meaning that, like murder, will out. If demonstration were needed that Mark Twain is sealed of the tribe of moralists, that is amply supplied by that masterpiece, that triumph of invention, construction, and originality, 'The Man that Corrupted Hadleyburg'. Here is a pure morality, daring in the extreme and incredibly original in a world perpetually reiterating a saying already thousands of years old, to the effect that there is nothing new under the sun. It is a deliberate emendation of that invocation in the Lord's Prayer “Lead us (not) into temptation.” The shrieking irony of this trenchant parable, its cynicism and heartlessness, would make of it an unendurable criticism of human life--were it accepted literally as a representation of society. In essence it is a morality pure and simple, animated not only by its brilliantly original ethical suggestion, but also by its illuminating reflection of human nature and its graciously relieving humour. In that exultant letter which the _Diabolus ex machina_ wrote to the betrayed villagers, he sneers at their old and lofty reputation for honesty--that reputation of which they were so inordinately proud and vain. The weak point in their armour was disclosed so soon as he discovered how carefully and vigilantly they kept themselves and their children out of temptation. For he well knew that the weakest of all weak things is a virtue that has not been tested in the fire. The familiar distinction between innocence and virtue springs to mind. And it is worthy of consideration that Nietzsche, and Shaw after him, both point out that virtue consists, not in resisting evil, but in not desiring it! 'The Man that Corrupted Hadleyburg' is a masterpiece, eminently worthy of the genius of a Swift. It proclaims Mark Twain not only as a supreme artist, but also as eminently and distinctively a moralist.