"I don't think I completely understand the theory, but, um – it's roughly because magic in our world doesn't give us much for free, the way your power does. You have to sort of tell it what to do, with concentration and will. Building a Gate onto a doorway gives you some existing structure to hang the magic off? And even more so if it's a stone arch that's been used to build a lot of Gates before, not sure why but it must somehow make the stone more prepared to hold the Gate-energy. Anyway, the usual method is to build the starting point threshold from an existing doorway, then hold a destination clearly in mind that has its own archway, and the spell sort of snaps to completion when it finds the location you want – like it's duplicating the structure you already built onto the other end. But if you don't have a doorway at the other end then I don't know what happens." 

"Huh. I don't have a good intuition for how your magic behaves at all."

"I've got intuitions, I guess. A good theory of all of it? Not so much. Leareth's worked on that." 

"What I'd really like would be enough intuition to have a workable number of moving parts in play when making guesses and extrapolations, and a good theory of it to check that against after pruning for stuff with potential."

“That makes sense. Hmm - what’s most confusing to you about it right now?”

"How it does information handling. Like - 'threshold' isn't a conjurable parameter. I have an intuition for what things are conjurable parameters and it is clearly different from what your magic cares about."

"...Huh. Bouncing that off my intuitions, I think maybe it's not the magic that cares? I think it's like I said, the magic has to be told what to do, but mages care about doorways and thresholds. I mean, there is a sort of stability that snaps into place once you have a complete threshold, but that's more like the way cloth is more stable than loose threads. It's the same sort of click as for completing a shield. But you have to hold all of it in your head, the departure-point and the search and where the other end goes, and...I bet it's a massive concentration-aid to just be able to point at the surface of a solid object and say 'the magic goes there', both at the departure and destination points. I'm not sure I even have a good enough visual imagination to hold just the concept of an archway in my head that way." He stops, frowns. "Does that make sense?"  

"Yeah, that makes sense. So being able to do it without a threshold would just imply being able to think of it without a threshold, essentially."

"If I'm right, yes. We should ask Leareth once he's back." 

"Which could be at any moment! Or in a thousand years! Fortunately I have his room number if it starts to look like a thousand years."

Vanyel chuckles. "Does that ever happen - time passing slower in the rooms? Seems like so far it's always been more convenient the other way." 

"I am not aware of a reason it cannot but it does seem to be convenient for us so far."

Nod. "Well, if goes longer than a usual full night's sleep, we could go knock or something. Did you have other questions about how magic behaves, in the meantime?" 

"Do spirits come up in any context other than the truth spell? What is their deal?"

"You can use them in a fight, fire-elementals in particular, but that isn't really part of the Heralds' school of magic, I just know how to banish them. Er, my understanding is that there are a bunch of other planes, with different physical laws but with mage-energy as a kind of universal fuel, and many of them have native inhabitants. They can perceive our plane, if only from some angles – that's how the vrondi work for the Truth Spell, they have an affinity for minds and can sense intent – and which can be summoned and given mage-construct bodies, the main case where I've seen that is Abyssal demons." 

"Huh - what's the significance of the bodies being mage-constructs?"

"I'm not sure! I think their actual bodies wouldn't be able to survive here, maybe. Just like ours can't survive there, but I think in some schools of magic, mages can project their minds to other planes." 

"It sounds like the various schools of magic do not talk to each other much."

"I guess not. A lot of them are really secretive – I know some things about Tayledras magic, for example, but in general they don't talk to outsiders at all." 

"What's the stated rationale?"

"Er, for the Tayledras it's that they have a sacred pact with their Goddess and lore from Her and they don't usually want strangers in the Pelagirs at all, much less learning their magic. For other schools... I mean, sometimes it's got to be political, or about holding onto power by keeping secret techniques. Rethwellan has a number of different mage-schools and I know almost nothing about them." 

"What a shame. I mean, cutting edge stuff being secret is one thing but it's sad if all these magic styles are just developing or languishing in isolation."

"...Does seem so. I'm guessing Leareth put a bunch of effort into finding out about lots of them, but also I doubt they made it easy." 

"Well, maybe some of them were easier to get in on the ground floor and he has ongoing access somehow, or something. Or maybe there'll be a huge magical renaissance after we're done with whatever we're gonna do here."

"That would be neat." Vanyel's lips tug into a smile. "Er, anywhere else your intuitions are confused about magic in my world?"