Patrick Parrinder 
Science Fiction [PDF ebook] 
A Critical Guide

First published in 1979. This volume presents Science Fiction as a coherent system, not as a collection of facts or random sequence of individual voices. The contributors are concerned with less with surveying the bare facts of the genre than with interpretating their significance. They attempt to establish the common properties of Science Fiction writing whether in the treatment of a theme or in SF of a given period or nationality.