Even though he should have been hard at work on The Winds of Winter, George R. R. Martin took some time out of his week to appear on History Channel’s new documentary event Superheroes Decoded, all about how today’s culture became so dominated by the creations of Marvel, DC, Dark Horse, and the like. Martin shared a fan letter he wrote to Marvel Comics, praising one of the issues of Fantastic Four, and the entire magazine.

Back in the days when comics weren’t the industry juggernauts they are today, they could publish some fan letters in their issues, with comments and responses from the comic creators themselves. Martin was a huge fan of Fantastic Four team member The Thing at the time.

Here’s the full text of the letter, which Martin says changed his life:

Dear Stan and Jack,

F.F. #17 was greater than great. Even now I sit in awe of it, trying to do the impossible — that is, describe it. It was absolutely stupendous, the ultimate, utmost! I cannot fathom how you could fit so much action into so few pages. It will live forever as one of the greatest F.F. comics ever printed, ergo, as one of the greatest of ALL comics. In what other comic mag could you see things like a hero falling down a manhole, a heroine mistaking a toy inventor for a criminal, and the President of the U.S.A. leaving a conference that may determine the fate of the world to put his daughter to bed. The epic story, spectacular and exciting as it is,  is not all that made this mag so great. The letter column was top-notch, too. I nearly died when I saw Paul Gambacchini’s letter. You’ve really made him change his tune; that letter was a far cry from the one printed in F.F. #9. Then there’s your cover boast — THE WORLD’S GREATEST COMIC MAGAZINE! Brilliant! You were just about the World’s worst mag when you started, but you set yourself an ideal, and, by gumbo, you achieved it! More than achieved it, in fact — why, if you were only half as good as you are now, you’d still be the world’s best mag!!!

And Stan Lee’s response:

We might want to quit while we’re ahead. Thanks for your kind words, George.

And look at him now, the boss of a giant franchise all of his own.

The first part of History’s documentary aired Sunday night, and the second part, which focuses on Marvel’s rise to stardom, airs on Monday. Game of Thrones returns July 16. The Winds of Winter will hit bookshelves maybe within this millennium, but there’s really no telling.

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