Sentence:  The <WSD>sercons</WSD> and Socially Conscious types smothered them in significant issues and realistic views. Without their fannish counterparts to balance them, these types swiftly went to extremes in Serious Discussion, until general fandom no longer resembled fandom of the fifties. That was years ago; today it still shows no sign of swinging back to a more genial and relaxed society. 
Meaning of the word marked with <WSD> tags:  A sercon fan; a fan interested in intellectual, rather than fannish, matters.