(Warning: The following contains major SPOILERS for the recently ended Game of Thrones season six, as well as discussion of a certain algebraic fan theory. Proceed with whatever level of caution your friendly neighborhood Three-Eyed Raven suggests is wise...)
Now, at this point, it's probably safe to assume that you've heard of the R+L=J theory, and how it relates to both Game of Thrones season six and might just fundamentally alter the future of Westeros in seasons to come. If not, though, then feel free to catch up on its inner workings right here, since, well, this whole article isn't going to make a whole lot of sense without knowing roughly what it's all about (essentially, Jon Snow isn't Ned's son at all, but rather the illegitimate son of Ned's sister Lyanna and Rhaegar Targaryen, hence R+L=J). As it turns out, though...
Game of Thrones Has Been Teasing R+L = J For Way Longer Than You Think
Specifically, since all the way back in season one's fourth episode. And when I say teasing, I don't mean 'having loads of main characters say enigmatic things about Jon Snow's parentage and destiny', though there was certainly plenty of that, Benjen.
Instead, I'm talking about an honest to goodness, full fat, 'how the hell did we all miss that'-type Easter egg, way back in the show's very first season.
Remember how, just after Jon and Sam Tarly first met, they met up and had a lengthy chat about how they both knew absolutely nothing about women?
Y'know, the one where Jon revealed that he'd once had the chance to sleep with recurring character Ros, and explained why he couldn't bring himself to sleep with her:
"I never met my mother. My father wouldn’t even tell me her name. I don’t know if she’s living or dead. I don’t know if she’s a noblewoman or a fisherman’s wife or a whore. So I sat there in the brothel as Ros took off her clothes, and I couldn’t do it. ‘Cause all I could think was, ‘What if I got her pregnant and she had a child, another bastard named Snow?’ It’s not a good life for a child."
Well, as it turns out, as Jon was discussing his issues with being a bastard, the show made a point of subtly drawing our attention to a pair of letters, carved into the wood behind his head:
The letters R, and L.
Which, moments later, we see framed in perfect R+L=J referencing fashion, as Jon walks around to join Sam on the other side of a table:
And so, there it is: R+L = J, in all its shiny, portentous glory. Way back in season one. Where...I guess we probably should have spotted it ages ago...
All we have to do now? Wait ten months of so till Game of Thrones returns for its seventh season. And now our watch begins...