In a similar way to Fantasy literature, Science Fiction represents prodigious creatures and phenomena that are also concurrently matters of beliefs (extraterrestrial beings, clones, high-power secret machines). The difference is that Fantasy calls on supernatural when Science Fiction is based on rationality and scientific likelihood. On both cases we deal with forms of belief. This paper shows inverse symmetry between writers’ and public attitudes. Authors emphasize the aesthetic side of extraordinary (the art of stirring the audience) and minimize the axiological side (their own belief or unbelief). On the contrary, public tends to select aesthetical works that confirm its axiological attitudes. We are led not to distinguish so radically between the sphere of belief and the field of fiction.