I wrote this more than 20 years ago, for David Hartwell’s critical review zine The New York Review of Science Fiction. I looked it up in connection with a new novel I have begun, tentatively, but almost certainly not permanently, entitled Sweet Home, and thought it might be worth reprinting.
Possibly the greatest American novel ever written.
Most of us would argue that science fiction has some special merits denied to most kinds of literature — for instance, its didactic ability to educate, or at least to motivate the desire to be educated, in science, its prophylactic qualities against future shock (if you read enough science fiction hardly anything ever takes you by surprise); its capacity for objective insights into the human condition — what Harlow Shapley called “The View from a Distant Star” 
Samuel Langhorne Clemens aka Mark Twain
However, it has recently come to me that there is another way in which science fiction has assets not shared by “mainstream” literature. What led me to think this was a period of reading a lot of Mark Twain, 
At first glance, it may seem improbable that the work of this man who died sixteen years before the first science-fiction magazine was published, and never wrote any of the stuff himself (let’s not get into some of his near-misses, like The Mysterious Stranger and Captain Stormfield’s Visit to Heaven, or that precursor of any number of L. Sprague de Camp novels, A Connecticut Yankee in King Arthur’s Court), has much to do with the subject. But I think it does, and to show what I mean, let’s consider The Adventures of Huckleberry Finn.
Everybody says Huckleberry Finn is Twain’s greatest work. A fair number of people (of whom I’m one) would even contend that it may well be the greatest American novel ever written. Nevertheless, almost everyone, myself included, feels that the climax of the book does not do justice to what has gone before.
If you haven’t reread Huckleberry Finn in the past four or five years you ought to do it now. It is one of the few books that can be read first at the age of ten, and then again every year or so for the rest of your life, finding new pleasures in it every time. The Duke’s attempt to reconstruct Hamlet’s soliloquy gets funnier the better you know the original. Huck’s relationship to his father, the numb acquiescence of the villagers in the Grangerford-Shepperton feud and its slaughter of the otherwise innocent members of both clans, the abortive lynching — above all, the nature of slavery, as given flesh in Jim — all these things become richer and more insightful as the reader does. The book is a boldly far-reaching triumph, that’s what it is, and any writer who doesn’t envy it is simply himself numbed into complacent ignorance.
But then at the last, when eighty per cent of the book has been a marvel, Tom Sawyer reappears on the Phelps plantation and concocts a lunatic humbug scheme to “free” the slave Jim, who, as Tom well knows, has in fact been freed already by testament of his late owner.
There are some funny, farcical bits in that ending. There are even a few touching ones. Nevertheless. The conclusion of the novel is an affront. Twain has touched our hearts with common human reality; then he pisses it all away in ten chapters of baggy-pants burlesque in which everyone behaves like a fool. There is only one word to describe the last one-fifth of Huckleberry Finn, and that word is dumb.
