The girl on the couch laughs. "Hi!" she says, poking her head up over the back of the furnishing. "Oh, wow, what bit you? This is an interdimensional bar! It has some really convenient properties like all of the books and also momentum-pausing which I'm guessing means nothing to you because if you lived in a world where that was a thing you would probably not have that particular configuration of scars."

"What about your world makes scars like mine unlikely? They're pretty unlikely in mine too..."

"You would've gone to a healing specialist or a sorcerer and gotten them fixed. Unless they didn't bother you at all and a sorcerer put them there to begin with and you didn't feel like calling in a better sorcerer, I guess."

"It's a fairy curse. Messing with fairy curses is a bad idea," he says. "And are you going to be as confused about fairy curses as I am about what you mean by momentum?"

"Yes, apparently." She smirks at some kind of private joke. "Tell me all about 'em."

"Fairies are a sort of person whom it is unwise to piss off," he says. "They can curse or bless people with various calamities or advantages. My father ran afoul of a fairy when he was young and stupid and earned himself a hereditary curse - he didn't know about the hereditary part until he had me, or he wouldn't have - my pain never fades, and if I'm stupid enough to have children, they'll be born with the same problem and a headstart of everything I've already accumulated. My mother got another fairy to bless me such that I can cope, but that one isn't hereditary and I wouldn't like my hypothetical kid's chances even if it were."

"That sounds inconvenient. And you don't want me to try fixing it?"

"Bad things happen to people who screw around with things fairies have done or given to people," he says. "Both in the sense that it tends to annoy fairies, and in the sense that fairy magic is just inherently a bad idea to mess with."

"Weird. Well, I'm glad you're coping."

"So, do tell me all about momentum, I might as well hear the interesting interplanar stories while I am in the interesting interplanar bar."

"So, in my world, everybody can do magic. Little mostly useless magic, more if they're cooperating. The more magic you do, the more you can do. But the dropoff is really fast. Sleeping's a huge hit to most people's momentum, you can cut it down by doing naps instead of a full eight hours but it still slows you way down. A day off is out of the question. But!" She gestures expansively at Milliways. "This place! Pauses momentum! I can't gain any here but I also can't lose it, I checked, I waited a few hours not doing anything and I can still," she turns invisible, "do this."

"It takes years to build up that much. Years of doing stuff, and it's easy to run out of stuff to do, if I'd been born someplace that had a sorcerer already I would've had to move or go nomadic as soon as I could fly because they'd be keeping all the work to themselves."

"...In what way is it easy to run out of stuff to do?"

"It can't be repetitive. You can do specialist momentum instead of sorcerer momentum, if you want, and just be a healer or an architect or something, and then you can take a whole weekend off if you want, but for sorcery you need variety. And it's harder to do things that people wouldn't want you to do, because they all have their own bit of momentum even if it isn't very much. And you need bigger and bigger projects. It is pretty easy to do all of the things in your momentum class that there are to do in a town in a week or three and then you have to go somewhere else, because you can't just wait for more stuff to crop up."

"And you can't just... okay maybe I shouldn't be getting into this," he says. "I know I'd probably be kind of annoyed with somebody coming in from another plane and asking me why I don't just."

"No, go ahead, ask me if I can't just. For all I know you have a refreshing new perspective and it will turn out that I can just."

"Well, since you asked. With my current understanding of the system and its restrictions, what I'd do is find somewhere to settle down where anyone living nearby knew to come to me with their actual problems, and then I'd - I don't know what you actually do with your magic - turn invisible and back again and construct and dismantle variously complicated magical dwellings and juggle fireballs and freeze and unfreeze small decorative ponds and grow a garden and create beautiful sculptures and destroy them in interesting ways and you can delete whichever of these specific suggestions are nonapplicable but the point is that unless there's a detrimental effect from undoing your own work, or something else I'm not thinking of, I cannot conceive of how it is possible to just run out of things to do. Run out of things to do that would be fully worthwhile on their own merits even if I didn't have to do them to keep my streak going, maybe, but that's a very different thing. So what am I missing?"

"Well, I do do things like that sometimes - frequently, even - as space filler. But it's legitimately difficult to keep up the variety that way alone - maybe it's that you're thinking of too many things as being different things?"

"Which things are different things, then?"

"The things you mentioned mostly are. Although turning visible again doesn't add anything - even maintaining invisibility pretty much doesn't except that you can't lose a power you are actively using by loss of generalist momentum, you'd just have specialist invisibility momentum left if you did that. But they aren't big enough. It's better than sleeping but it won't get you to sorcerer level - defined depending on locality as either flight or water breathing by generalist momentum alone. You need big stuff at sorcerer level - landscape-altering things at least every now and then."

"...I'm a little afraid that if I try any harder to figure this out I'm going to encourage some very bad mental habits in myself," he says. "But it's an interesting problem and I definitely think there's some kind of perspective issue at work here even if I can't quite tell what it is."

"Bad mental habits?"

"In my world - it sounds very much like yours doesn't have this problem, for which I congratulate you - hubris is a lethal character flaw, and I do mean that literally. I'm pretty sure that before I turn thirty I will have either died of it or ascended to the category of people whom everyone else has to worry about being hubristic near."