The world of the book isn't Alternate Universe
It's the future! Think about it: when global warming causes the seas to rise, the USA could easily become islands, and if there were to be a nuclear apocalypse/ WW3 then civilisation would probably step back a few millenia or so. Presuming Korea came off the better power they would have it in their sights to take over the world. Though it is set in the early 20th century, a few years out of the Victorian era, the years could be numbered from a new starting point: perhaps when civilisation became clever enough to map out time and separate it into lengths again, or from when the big war ended, or from when the measurements of the past were re-discovered?It's set in the same world as something else
- Harry Potter
- As stated on the main page, Rithmatics can be compared with Arithmancy: but what if it is Arithmancy and they just don't know it in America yet at that point?
- Nalizar could be a young Snape before he's discredited and has to adopt a new identity and life: but he doesn't change his ways. We know that people like Dumbledore got very old (even without the Philosopher's Stone), so Snape/ Nalizar could.
- ChalkZone: what happens when our Kid Hero grows up and needs to use sentient chalk drawings to protect himself from bloodthirsty ones?
The Scribbler used more than just the two new lines
- The question of how the children disappeared was resolved, but how the Scribbler got to them isn't made clear in the cases of Calloway and Linton - did the Scribbler sneak into the knight-senator's house with all the security around? He has the Line of Silencing, but he'd also need not be seen. It's possible that he used a portal as in Pan's Labyrinth.
The chalklings were created or awoken by the Native Americans
- Sanderson's descriptions of the chalklings (and to a lesser extent the other Rithmatic drawings) evoke the petroglyph art of some Native American peoples of the Southwestern USA, and Joel reads about Spanish explorers finding Rithmatic drawings in "Zona Arida" (Arizona). Perhaps the Native Americans accidentally created the first chalklings and then were mostly wiped out or driven south by them (as is hinted) which might also have something to do with why America is shattered into islands.
There's a Sixteen-Point Circle
- All of the previous circles have geometric reasons for how many points they have and where the points are places. The two-point circle is based on the circle's diameter, the nine-point circle has bind points based on a non-obtuse triangle, etc. The story makes it clear that people don't know everything about rithmatics, so it stands to reason that there are more circles that they don't know about too. Why a sixteen-point? It's bind points are the points on the unit circle.
- Every known type of circle (plus a couple extra) can be derived by manipulating the dimensions of the triangle that gave you the nine-pointer (yes, even the two-point circle). a 16-pointer, on the other hand, cannot.
Joel would have become a Rithmatist if he had not been holding a coin during the second ceremony.
- It is mentioned that circles and gears drive chalklings away, and the mysterious creature that appeared in the room with Joel seemed to be driven away when he brought the coin out of his pocket. My theory is that the chalklings that manifest during the ceremony somehow join with the participating children they choose, or at least must come close to them in order to pass on the power to manipulate in such a way. If Joel hadn't been carrying that coin, or at least hadn't brought it out of his pocket, he would (or at least could) have become a Rithmatist, as he wished.
- Of course, buttons and the like would be on some clothing, but they presumably aren't strong enough to break potential connections.
Some group is blocking Joel from becoming a Rithmatist
Joel's father died under suspicious circumstances close to initiation day. Later in the year, Joel was given a botched ceremony at the wrong time and in the wrong place. And when he goes for a late initiation, it's by the same person, and if the above theory is correct, the priest should have known to ask to remove all clockwork. The people who Trent owed money to didn't kill him
Maybe they would threaten his family, but killing someone who owes them money would only ensure that they'd never get their money. Especially if he was on the verge of a breakthrough. Unless it was Joel's mother who owes them money, and she lied to Joel.