Defining Science Fiction

George Hay ("futurologist")    
Brian Aldiss (science fiction writer)    
H. G. Wells (polymath)    
Eric Rabkin (tri-partite definition)    
Frederic Brown (science fiction writer)    
Eric Rabkin (theoretical definition)    

Eric Rabkin:

Science fiction has three focal qualities:
1) the fantastic made plausible
2) high adventure
3) intellectual excitement

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