From Metamorphoses of Science Fiction, pp. 23-24:

Usually the symbiosis of popular science and juvenile adventure finds it impossible to mimic SF without regressing into their homologue of the fairy tale, with its victorious hero, foiled villain, damsel in distress, and quaint helpers or marvelous helping objects. Such sub-Vernean or Gernsbackian SF does not change the fairy tale structure but only the motivation of its devices: it pretends to explain away the supernatural by reassigning it to natural science and noble scientists (who are energetic and sentimental if young and in love with, absent-minded if old and fathers of, the eternal feminine). However, the science is treated as a metaphysical and not physical, supernatural and not natural activity, as gobbledygook instead of rational procedure. From Ralph, Buck Rogers, and the post-Stapledonian supermen to Asimov’s psychohistory (which has at least the advantage of identifying the proper field of modern destiny, social relations), such metaphysical gobbledygook vitiates some of the best-known SF works. … In the perfectly just world of taste and poetic creativity, this procedure reaps the reward of hypocrisy: fairy tale readers rightly prefer the classics, sophisticated SF readers disbelieve the fairy tale. Inversely, in the very imperfectly redistributive world of social taste and commercial SF, such a procedure breeds generations of readers with juvenile taste, unable to develop the standards by which to judge SF (not to mention empirical human relations).