Wollheim begins contrasting the nationalism and technology oriented stories of Jules Verne with the Uuopian and idealistic ones of H. G. Wells (for me The Time Machine warns of the exact opposite of those traits) and follows with reviewing the careers of those he considers major benchmark authors of the genre: Olaf Stapleton, Isaac Asimov, A. R. Van Vogt, Robert Heinlein, Arthur C. Clarke, E. E. Smith, etc. The New Wave of the 1960s was also much on his mind and he negatively notes its renunciation of the previously assumed optimism of the genre. Much food for thought concerning the author's discussed. Wollheim's career as a writer, editor, and publisher was concurrent with those discussed; 49 years have passed since than and its good to be reminded of the schools of thought, viewpoints, and controversies running through the works of basically the first 50 years of science fiction in the western world. ( )

Good non-fiction analyzing sci fi & mentioning good authors.
Noted during my 1980's attempt to read every book in my small town library. ( )