From a 1980 Phillip Roth interview with Milan Kundera, shortly after the translated version of Book of Laughter and Forgetting was published:

PR: Laughter has always been close to you. Your books provoke laughter through humor or irony. When your characters come to grief it is because they bump against a world that has lost its sense of humor.

MK: I learned the value of humor during the time of Stalinist terror. I was 20 then. I could always recognize a person who was not a Stalinist, a person whom I needn't fear, by the way he smiled. A sense of humor was a trustworthy sign of recognition. Ever since, I have been terrified by a world that is losing its sense of humor.

PR: In your last book, though, something else is involved. In a little parable you compare the laughter of angels with the laughter of the devil.....

MK: Yes, man uses the same physiologic manifestations--laughter--to express two different metaphysical attitudes. Someone's hat drops on a coffin in a freshly dug grave, the funeral loses its meaning and laughter is born. Two lovers race through the meadow, holding hands, laughing. Their laughter has nothing to do with jokes or humor, it is the serious laughter of angels expressing their joy of being. Both kinds of laughter belong among life's pleasures, but when it also denotes a dual apocalypse: the enthusiastic laughter of angel-fanatics, who are so convinced of their world's significance that they are ready to hang anyone not sharing their joy. And the other laughter, sounding from the opposite side, which proclaims that everything has become meaningless, that even funerals are ridiculous and group sex a mere comical pantomime. Human life is bounded by two chasms: fanaticism on one side, absolute skepticism on the other.....

Totalitarianism is not only hell, but also the dream of paradise--the age old drama of a world where everybody would live in harmony, united by a single common will and faith... once the dream of paradise starts to turn into reality, however, here and there people begin to crop up who stand in its way, and so the rulers of paradise must build a little gulag on the side of Eden. In the course of time this gulag grows ever bigger and more perfect, while the adjoining paradise gets ever smaller and poorer.

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MK: Through the last section of the book.... resounds the contrary kind of laugh, the kind heard when things lose their meaning. There is a certain imaginary dividing line beyond which things appear senseless and ridiculous. A person asks himself: Isn't it nonsensical for me to get up in the morning? to go to work? to strive for anything? to belong to a nation just because I was born that way? Man lives in close proximity to this boundary, and can easily find himself on the other side. That boundary exists everywhere, in all areas of human life and even in the deepest, most biological of all: sexuality. And precisely because it is the deepest region of life the question posed to sexuality is the deepest question. This is why my book of variations can end with no variation but this.

PR: Is this, then, the furthest point you have reached in your pessimism?

MK: I am wary of the words pessimism and optimism. A novel does not assert anything; a novel searches and poses questions. I don't know whether my nation will perish and I don't know which of my characters is right. I invent stories, confront one with another, and by this means I ask questions. The stupidity of people comes from having a question for everything. When Don Quixote went out in the world, that world turned into a mystery before his eyes. That is the legacy of the first European novel to the entire subsequent history of the novel. The novelist teaches the reader to comprehend the world as a question. There is wisdom and tolerance in that attitude. In a world built on sacrosanct certainties the novel is dead. The totalitarian world, whether founded on Marx, Islam or anything else, is a world of answers rather than questions. There, the novel has no place. In any case, it seems to me that all over the world people nowadays prefer to judge rather than to understand, to answer rather than ask, so that the voice of the novel can hardly be heard over the noisy foolishness of human certainties.