The DADA riddle from Harry Potter and the Philosopher's/Sorcerer's Stone

 I was having a conversation recently with a friend who's kid is reading the Harry Potter series, and he was asking about theories that the school motto has a one-word-per-house code for the four houses, and I was saying that dragon as Slytherin and tickle as Gryffindor, maybe, but the other two are really hard sells, but that it was definitely worth asking, because she definitely does do a lot of coding, and then I was saying that there is even stuff that has been discussed as coding among commenters but didn't seem to pan out tightly in the end, so maybe she included something originally in a form that she might be able to pick up in code but then didn't follow that, and I was mentioning the theory of the potion riddle in book 1 just before the mirror chamber being a code for the seven DADA teachers across the seven years, because I have never really read much more about that panning out as a major code thing (but then I am also fairly reclusive from the online commentary sphere, not because I don't like it; I just am kind of reclusive in general and usually trying to catch up on work because I'm not super organized). 

But then I was going through it and actually it does work out pretty neatly. The three killers in line are those working directly with Voldemort: Quirrel in book 1, Barty Jr. in book 4, and Amycus Carrow in book 7 (I think that one of the reasons the theory may have at least lessened in fervor is that, in the last three book, our expectations became much less about new individual books and their elements that might fit into a numbered series of books and more about the forecasted culmination of the overall story arc ... so we don't think of Carrow as being one of the seven teachers because he's not a legit teacher, just part of the takeover, so it feels kind of like book 7 went into territory where the whole "seven teachers in seven years" has been sort of wiped out in the whole main arc of the takeover of the whole Wizarding World). The two nettle-wines are then the two who went batty, literally had a cognitive breakdown of some sort, at the end of their books, Lockheart and Umbridge. 

And that leaves Lupin and Snape. There, admittedly, one has to go into theme to make the matches, rather than simply material aspects like working directly with Voldy or going nuts, but at some point, at least I believe, these things must tie out with theme and character in some way or another if they are to be interesting at all as part of the artistry of the work and not just structure for structure's sake. Lupin is one of the key ways Harry connects with his past, like the potion that allows going back through the first set of flames, and discovering and reconciling with the truth about Snape is necessary for Harry to move forward as a person. But, while the forward and backward thing has to go into theme and specific characterization, the basic aspect of movement in general, movement of any kind, is a bit closer back to material detail, although more on the "what does literature as such do?" (versus "what do these particular themes or characters in this particular work do?"): These two DADA teachers were key to the movement of the character as protagonist, progression along his character arc in the narrative arc.

I don't see the riddle correspondence as heavily tied to chiasm, although the biggest chunk is chiastic (whether intended or not, but I suspect probably or at least highly possibly), in that the group with the largest membership, the three killers in line, happen in books 1, 4, and 7 ... but the rest of them don't tie out: nettle-wines are 2 and 5 and helpers are 3 and 6. Although, it is interesting that, while not mapping onto the seven-book chiastic structure, the wines and helpers do pair in elements of their books: we meet Lockheart again in Umbridge's book, and in book 6, Lupin is a key source Harry tries to tap to figure out the truth about Snape's old positions book (and not that, in book 7, which ends with the Prince's Tale chapter of finally understanding Snape, we have a tense refusal of Lupin's help, which I think makes a sort of tension between these two in Harry, moving on from the past to find the future ... and obviously beyond ... a lot more latent is the fact that, in the epilogue, the boy Harry names for Severus Snape [at least the middle name]), that boy is in the same family unit with the son of Lupin, Harry's godson ... so the connection between those two as DADA teachers for Harry is strong (and really, one could Harry's second son as an embodiment of the DADA teacher theme even in the first name, in that it is for Harry's real DADA teacher throughout the series, and materially his sort of DADA independent/directed study professor in book 6, to put it in literal real-world college/grad-school terms).

All that to say, I think the DADA riddle does wind up being something, and I think she may have tied it loosely to chiastic structuring (the killers) but not seriously tightly (neither the nettle-wines nor the helpers), although I do think there is some evidence she may have intended pairing as an element with the types, just not all tied tightly to that full chiastic structure (you can't tie everything out that tightly and get it all in; different mechanisms will always crowd each other a bit when the work is as densely packed with meaning mechanisms as she does). Fun discovery though, long after the fact (although, who knows, with as little as I keep up on things, others may have put it together when book 7 came out ... come to think of it, I would be highly surprised if I am the first ... highly surprised).