One of the complaints leveled against many works of science fiction is that the aliens and artificial intelligences who appear in the genre are simply too much like us, little more than human beings in funny bodies (or, for that matter, in human bodies with funny heads). This is particularly obvious in relatively unsophisticated science-fiction films and television shows such as Star Wars and Star Trek, where the creation of truly nonhuman aliens runs into both conceptual and practical difficulties, but it is also the case in many science fiction novels and short stories that have long been recognized as classics.

Some writers have argued that it is difficult, perhaps impossible, to envision an intelligence that is truly different from our own. It has also been suggested that the creation of such a thoroughly nonhuman intelligence in a work of fiction might in fact be undesirable...