As in: love or hate JRR Tolkien as you please, but you may not ignore him when it comes to the fantasy genre. Venerate or despise HP Lovecraft for any number of reasons, but when we talk about horror we are ultimately using concepts and conceits that he defined and developed. But if there’s a single figure of the science fiction field that similarly towers over the landscape, I do not know his or her name. Bob Heinlein comes close. So does John Campbell, although that would have been more true thirty years ago. Maybe Gene Roddenberry and George Lucas, combined. Other than that, though, I’m stumped.