Although some of the contradictions [in Blish's Cities in Flight tetralogy] surely result from authorial carelessness, forgetfulness, or indifference, they are too numerous and too prominent to be regarded as anything other than an essential feature of the overall story. Since point of view is rigidly controlled throughout the work, every statement can be attributed to one or another of the various characters. Given this fact, we can make sense of the tetralogy by regarding it, not as a fiction in which a universe has been created by an omniscient, omnipotent author, but as historical narrative with a large admixture of myth; that is, by assuming that behind the sometimes accurate, sometimes erroneous, sometimes mythical narrative there is an actual history….

[The] explicit Spenglerianism of Cities in Flight is erroneous in one of its details, highly dubious in others … and rather absurd overall. The flat error is in the statement by Robert Helmuth that the building of the pyramids (which occurred in what Spengler considers the Egyptian spring-time) was "the last act of an already dead culture."… The overall absurdity lies in … the idea of the "cultural morphologist":

Chris recognized the term from his force-feeding in Spengler. It denoted a scholar who could look at any culture at any stage of its development, relate it to all other cultures at similar stages, and produce specific predictions of how these people would react to a given proposal or event….

                                     (pp. 177-78)

Spengler never uses the term "cultural morphologist," and he would surely never have imagined that his work could be put to any such narrow uses. If cultures are organisms, you can make for a culture predictions of the kind that can be made for any organism…. As a matter of fact, the cultural morphologists of Cities in Flight never actually practice their trade: the various "cultures" with which the heroes deal are never presented with enough fullness to allow for any kind of Spenglerian assessment; the various stories turn on coincidence or on individual psychology of a rudimentary sort and would not be essentially different if explicit references to cultural morphology were entirely eliminated—which could be done by deleting a handful of sentences.

But to say all this is not to say that Cities in Flight is of no interest to the student of Spengler. The first volume gives us an intelligently Spenglerian view of the near future, and the other three, albeit very sketchily, the life story of a Spenglerian culture. In comparison with most science-fiction novels and series, Cities in Flight is a very rich work indeed. (p. 178)