Le court essai écrit par H. P. Lovecraft présente des lignes de conduite pour écrire une histoire interplanétaire réussie. Sans être un ouvrage critique à proprement parler, le texte nous indique ce qui, selon Lovecraft, était déjà de l’ordre du trope narratif de son époque pour les histoires de science-fiction tout en exposant les objectifs qui sous-tendent la figure de l’extraterrestre pour l’auteur.
Extrait : « It is not necessary that the alien planet be inhabited—or inhabited at the period of the voyage—at all. If it is, the denizens must be definitely non-human in aspect, mentality, emotions, and nomenclature, unless they are assumed to be descendants of a prehistoric colonising expedition from our earth. The human-like aspect, psychology, and proper names commonly attributed to other-planetarians by the bulk of cheap authors is at once hilarious and pathetic. Another absurd habit of conventional hacks is having the major denizens of other planets always more advanced scientifically and mechanically than ourselves; always indulging in spectacular rites against a background of cubistic temples and palaces, and always menaced by some monstrous and dramatic peril. This kind of pap should be replaced by an adult realism, with the races of other-planetarians represented, according to the artistic demands of each separate case, as in every stage of development—sometimes high, sometimes low, and sometimes unpicturesquely middling. Royal and religious pageantry should not be conventionally overemphasised; indeed, it is not at all likely that more than a fraction of the exotic races would have lit upon the especial folk-customs of royalty and religion. It must be remembered that non-human beings would be wholly apart from human motives and perspectives.
But the real nucleus of the story ought to be something far removed from the specific aspect and customs of any hypothetical outside race—ought, indeed, to be nothing less than the simple sensation of wonder at being off the earth. Interest had better be sustained through accounts of bizarre and un-terrestrial natural conditions, rather than through any artificially dramatic actions of the characters, either human or exotic. Adventures may well be introduced, but they should be properly subordinated to realism—made inevitable outgrowths of the conditions instead of synthetic thrills concocted for their own sake. »