Okay, how many science fiction novels from the 50's have REALLY stood the test of time? 'More Than Human' is devoid of slimy aliens, ray-guns, faster than light travel, time machines, robots, or any of the other "stereotypes" non-sf people associate with 50's science fiction. Well, what DOES it have going for it? How about:
Sturgeon was a thinker with a tremendous imagination. I caught myself grinning often at several of his lines, at how he avoided clichés and gave fresh ideas to simple scenes and concepts. In the first section, "The Idiot," I was reminded of the opening of Faulkner's 'The Sound and the Fury.' (Yes, comparing Sturgeon to Faulkner is NOT a stretch!) The way Sturgeon gets inside Lone's head and lives there is amazing. Wonderful writing that still reads with freshness 50 years later.
Six misfit outcasts, each with a unique gift, form a new step in man's evolution, a gestalt of unbelievable power. I won't go into the social, political, and moral implications of such an idea (Read the book), but the concept by itself is interesting. What Sturgeon does with it is fascinating.
I have not researched Sturgeon very much, but from what I have gathered, he was somewhat of a rogue who loved to examine the dark side of the human psyche. This and his inability to be confined to a nice neat label come across in the writing to present a story that is exciting, awe-inspiring, and most important, honest.
If you've only read a few sf writers from the 50's (such as Asimov, Clarke, Bradbury, Bester, Simak, etc.), expand your horizons with Sturgeon. You won't be sorry.