Okay here’s my headcanon as I rewatch CQL: Jiang Yanli figured out the golden core transfer.
And the main reason I like to believe she worked it out is because for me it adds to the sense of tragedy, that the one person who realises is also the one person whose realisation wouldn’t change anything.
Not even just in a ‘fix-it’ sense, but in that, given (my reading of) her character, I genuinely think the story would play out exactly the same whether she knows or not. And so it adds to this landscape of well-intentioned and capable and flawed people trying their best, and yet ending in disaster as those flaws and good intentions collide in the worst possible way, so you end up with something that feels like both inevitable and preventable tragedy.
But I also just feel like it makes sense for her to figure it out. Aside from Jiang Cheng, she’s the person with the most information about what happened. Like, does anyone else even know about Jiang Cheng losing his core to Wen Zhuliu? Wen Chao may have boasted about it, and maybe some of the Wen soldiers at Lotus Pier would know, but beyond that it would just be another rumour, and then Jiang Cheng turns up golden core intact and ready to help fight. And even if some people do believe it, how many would ever consider the possibility of someone else giving up their own golden core? How many would make the link from the thought of an unprecedented self-sacrifice to the arrogant and mercurial Wei Wuxian?
Lan Wangji, maybe, could put it together if he had all the pieces. But, crucially, at least in CQL canon I don’t think he ever actually knows about Jiang Cheng losing his core. Who’s going to tell him? Jiang Cheng? It would feel too much like a weakness, and even believing he was healed by Baoshan Sanren is too mixed up with Wei Wuxian and their relationship.
But Jiang Yanli knows about Jiang Cheng’s core. And Jiang Yanli was there all those days (weeks?) in Yiling while Wei Wuxian ran himself ragged trying to find a solution. And then Wei Wuxian cries on her shoulder and next thing she knows she’s waking up in a carriage bound for Lanling and accompanied by Song Lan, whose injury was mysteriously ‘healed by Baoshan Sanren’, and then her previously-coreless brother turns up healthy and powerful and her recklessly self-sacrificing brother is missing. And if that’s not enough to work it out, three months later said recklessly self-sacrificing brother shows up without an explanation or a sword or more than a ghost of his brilliant smile, wielding a flute and a strange power and a cold cruelty, flinching away from contact or comfort.
Jiang Yanli can do basic maths.
And yes, Jiang Cheng has all the same pieces of information but the crucial difference, I think, is that Jiang Yanli is not directly involved; she’s neither donor nor recipient. Wei Wuxian’s lies were so carefully tailored to Jiang Cheng specifically: just the right amount of exactly what he needed and wanted to hear (because when you’re desperate, you don’t look quite as closely for the catch) and a quest to prove himself that involved just enough complexity and subterfuge to convince him that it wasn’t too good to be true. Jiang Yanli has the clarity Jiang Cheng doesn’t, because it’s not her golden core. She’s not the target audience, and there’s a reason Wei Wuxian opts to send her away: the lies that work on Jiang Cheng aren’t going to work on his shijie and he knows it.
Add to that the fact that I think a large part of the reason Jiang Cheng doesn’t figure it out is… the form of denial that serves as a kind of self-preservation. It’s a very human thing to do: we deceive ourselves or avoid looking too closely at things we don’t want to see or know or realise, because doing so would hurt us. So on some subconscious level I think he doesn’t let himself question the golden core situation too closely, or put some of those pieces together. Whereas for Jiang Yanli, again she has that one vital step of removal, and so is able to put some of those pieces together without flinching away or risking it shattering her entire sense of herself.
And at the end of the day, Jiang Yanli knows her brothers. She has watched them grow up, knows their tendencies and their tells. She knows what they would do for one another, and what they would do to one another.
She has the pieces of the puzzle, and the intimate knowledge of those who made it, and the necessary perspective to figure it all out.
So then we come back to the part that really sells me on this, which is that it doesn’t change anything.
Oh, we see her concern for Wei Wuxian, and we see her ever so gently pointing out that he’s changed, but just as gently demonstrating her continued and unconditional love and support. We see her circumspectly asking Lan Wangji, as she tries to figure out how she can help her brother. We see her deflecting Jiang Cheng’s irritation with him when he wanders off, first in Qinghe and then in Yunmeng. We see her again and again doing everything she can to just be there for him–for both of them.
And all of these can be read as Jiang Yanli knowing… but they’re no different, I think, than the things she would do if she knew Wei Wuxian was hurt or struggling in any way.
Also, she doesn’t have a way to fix the problem: Wen Qing is missing, for one, and Jiang Yanli is in the relatively unique position of loving both Jiang Cheng and Wei Wuxian, equally–and pretty much any potential ‘solution’ is going to cause some pain or risk to at least one of them, so she’s not going to, say, look for a way to reverse it.
So, in absence of a way to fix it without somehow making it worse for one or both of them, I think her calculus would be similar to Wei Wuxian’s: Jiang Cheng cannot know. (If she had found out before it happened maybe it would be different, but this isn’t that kind of what-if).
In the aftermath, unable to change the outcome… once again, she knows her brothers. She knows it would break Jiang Cheng. She knows the relationship between her brothers is already messy, especially after Sunshot (and understands better than most the reason for and shape of that mess), and that such a revelation could risk irreparably damaging it. She knows, too, that to reveal something like this would potentially put Wei Wuxian at risk, because there are those who would see it as a weakness and a target.
(If she survived Wei Wuxian’s death… perhaps, eventually, she would tell Jiang Cheng, and help him through the initial hurt of it, and guide him to see it as a lasting sign of Wei Wuxian’s love, bittersweet and complicated as it may be. But this is not that kind of what-if).