"Yeah."

"So you can in principle run any white arts spell on any positive emotion but the results will come out differently based on exactly what you're using - and who it came from, we have less reason than black arts witches to use someone else's emotions but we can, because everyone feels things differently. There's one specific guy in Australia who has the best quality sense of humor for fixing a specific blood disorder, and that's just the most famous one."

"Huh, how much more effective is it to use that guys sense of humor than then average sense of humor?"

"If you happen to be treating that exact blood disorder about a factor of fifteen, but it's not especially good for anything else it's been tested on."

"-huh, how feasible is it to find more instances of things like that?"

"It's hard! That one was discovered in a complete fluke. But there's been a lot of testing for certain cancers and stuff and we've found some factor of, like, five, variance, doing it that way, and there have been more flukes with more extreme results."

"How hard is it to test for?"

"Most of the overhead is getting someone into the collection booth and in the right mood, but that's surprisingly hard to do at scale."

"-hrm, this sounds like an interesting logistics problem.... are there easy ways to provoke emotions that could use more testing? Can you test for a bunch at once?"

"You can only test what you actually store, so if what you store is a complicated cocktail, that's what you get, not several different crystalsful of whatever separate ingredients were in the emotional state. Different people vary in what's easy to provoke and how!"

"Hrm, this does sound rather difficult to scale."

"There was an experimental theater production which tried to arrange their show so they could try to elicit emotions with it while the audience was all in collection but it did not work that well, usually you have people watch movies - often picking their own, since, again, variance."

"How obtrusive is it to test people? Could someone set up movie theaters that are free so long as the audience is okay having their emotions distilled?"

"You need them all in their own booth. Prevents having more than one row unless you go for really aggressively stadium-style, so it'd be expensive to build, and you couldn't sit next to anyone you went with, and you'd probably still get takers but you wouldn't want repeat takers showing up just for the free entertainment, if you were trying to do this for testing. Also doesn't filter at all for willingness to follow up on regular donation."

"How inconvenient is regular donation? Can you pay people for it?"

"I mean, you have to show up to a place and get into the specified mood on demand, it's not more inconvenient than that makes it sound, but most people don't want to, and it does tend to affect the quality of emotions to pay for them."

"Can uh, dru-um."

"...what?"

"Um. I was going to ask if drugs work." Which is maybe insensitive to bring up given the circumstances but he's not really sure what else to say.

"They don't distill. They're localized differently. They can sometimes help - if someone's too anxious to be happy then taking an anti-anxiety med will let them distill happiness."

"Ah, that makes sense. What does it mean for them to be localized differently?"

"Uh, authentic emotions are generated in the soul and only cause physiological sequelae, drug-induced ones go the other way."

"Ah.... are there resources on magic which are as good at explaining it as you are?"

"...there's textbooks and websites I like, but I'm not copying my exact words from anywhere in particular."

Nod.

"When I've tried to look for things I havn't found anything that seemed like both a good entry point and ... clear headed."