Most readers of Kurt Vonnegut’s novel Slaughterhouse Five obviously do not feel that the alien abduction subplot diminishes the novel. For these readers, the subplot adds to the humor, mystery, whimsy, and philosophical depth of the book. The subplot is probably one of the elements that made the book appealing to many of its first readers and that has helped make the novel continue to be appealing in the decades since.
Vonnegut’s decision to include aliens in his novel must also have seemed a daring fictional innovation at the time, at least for those readers unfamiliar with science fiction. Public interest in flying saucers and the potential of life on other worlds – as well as visitors from those worlds – was quite keen when the novel was first published. To incorporate such material into a book intended for an audience beyond fans of science fiction must have seemed intriguing when Vonnegut first wrote. This would probably have seemed especially the case in view of the novel’s concern with such other, more apparently “serious” issues as World War II, the mass destruction of human life, and general matters of war and peace.
For some readers, however, the alien abduction subplot will seem an exercise in gimmickry. These readers will probably feel that Vonnegut, in an effort to be clever and witty and innovative, diminished his book by making it seem shallow, superficial, and “popular” in the worst senses of the word. For readers such as these, quotations such as the following will seem lacking in much literary distinction and/or philosophical depth:
“If I hadn’t spent so much time studying Earthlings,” said the Tralfamadorian, “I wouldn’t have any idea what was meant by ‘free will.’ I’ve visited thirty-one inhabited planets in the universe, and I have studied reports on one hundred more. Only on Earth is there any talk of free will.”
Readers who feel this way about the book, however, are far more likely to ignore the novel than to read it, re-read it, and condemn it in any great detail. To adapt a popular phrase, the novel “is what it is.” It will appeal to some readers and not to others. To adapt a phrase both popular and ancient, there is little point in arguing about different tastes.