Karen is informed by owl that she's a prefect. She writes her friends about that, of course.
"Uh, fourteen, I guess, but I wasn't sure I'd go for it either at first - it's just something where you want the information, it's better to have it and not need it -"
"The correct answer," he complains to Minor, "is that you can quantify the hit to someone's social standing from a scandal or a dubious association or a Muggle relative by looking at marriage agreements between families trying to compensate for one of those things, and it's quite reasonable to expect someone to compensate their siblings for the damage done to their prospects -"
"Yes, that would be the way to do it such that Michael incurred the costs of being Michael instead of accidentally spreading them around."
"But he's already trying to save up to move out - wouldn't it be costlier in some ways if he took longer to do that -"
"I mean, if I separately derived value from him not living at home then I could give him money for his house but it really should be separate."
"I feel like if he could get money via you valuing him not living at home you might have a problem."
"- yeah, possibly. Anyway, marrying Muggles should not involve reputation costs accruing to all your blood relatives, that's dumb, so people who know it's dumb mostly just handle it by pretending it doesn't."
"It'd take people who don't think it's dumb agreeing that it's dumb, it wouldn't be enough for all the people who think it's dumb to ignore it. Ignoring things isn't a great way to make them go away anyway - what you could do is fund a trust of some kind that pays out the reputation cost to everyone involved -"
"If you do enough of that sort of thing it starts looking like a, what do they call it, a dowry?"
"I think dowries are reasonably sensible. Things that are acknowledged to use currency end up less discriminatory than ones that implicitly use currency or mostly use social currency."
"If the end result is more Muggle marriages then I think that's probably all for the better."
"Unless they work out badly because they don't actually like each other and then everyone's turned off the idea."
"I'm not sure how that's made more likely by changing exclusively the thing where your marriage choices affect your siblings' prospects of getting married themselves. Direct incentives to marry Muggles might make for less happy marriages because incentives for anything other than happy marriages will do that a little, but if people are currently excessively unwilling to marry Muggles then it might do the exact opposite."
"I'm not sure there's a specific amount of willing people in general ought to be - it depends on how good they'd be at picking a Muggle, and what everyone else would think of it -"
"Yeah. I just think as a general principle that if you count all the costs and try accounting for them you end up better off than if you pretend they don't exist, and the directions you'd get pushed in by accurate cost-accounting are mostly the right directions to be pushed in - just like giving people more true information might make them make stupid decisions but the presumption's the other way -"
"How do you price in things like Rebecca having that idea to do a locket enchantment on a bunch of things to do remote concerts?"
" - I mean, if Michael figures that out then he'll sell them and they'll be very rich, that's how you price it in. I'm glad Michael married Rebecca, they're so cute together and they're happy, the point of 'keep track of costs' isn't that you'll find they're not well worth it."
"- that's not what I meant but I don't know how to say what I meant. They're really cute, yeah."
"I'll probably marry a Muggle, I don't like anyone at Hogwarts the right way. But I would be annoyed if I'd liked someone and then Michael's shenanigans meant I couldn't marry her, so I'm going to make sure not to do that."