## Integers, fractions and inequalities

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"Why would anyone want to be in Slytherin?" Steve asked his companion as they passed the Slytherin common room. "I mean... Voldemort was a Slytherin, the Gaunts and the Malfoys were Slytherin. Do they just all end up evil or something?"

Bruce merely shrugged, fingering his blue collar and looking vaguely uneasy as he remembered the sorting hat's words. ...What about Slytherin, then? You could be powerful in the extreme, see a whole new side to yourself... If Rogers was right, did that make him a little bad too, even though he was in Ravenclaw?

"Maybe Slytherin's just where they lob all the bad eggs?" Steve suggested.

"What the... where do you get off, talking about us like that?" came the indignant response from behind them. They turned to see a short, dark haired fifth year stood behind them, scowling at the Griffindor. "How come you get the right to judge us all based on the actions of a few people?"

Steve took a step back, immediately going on the defensive. "How come every evil wizard has been in Slytherin then?" he challenged, folding his arms.

The Slytherin rolled his eyes. "Sure, because when you divide elements up by property you don't see clusters of results at all right? But if you focus on one set of data and ignore all other results then you're bound to miss something."

Bruce blinked. That was... actually, that was rather good. "You know, Steve, he does have a point," he murmured.

"Damn straight I have a point, big guy." the boy replied, favouring him with a grin.

"... great." the boy said dryly. "Ok... well, you ever do that trick with vinegar and bicarb in lower school, yeah? Well think of it like this: everyone can have a beaker of vinegar, and  little packet of something, and people are put into groups based on what colour of stuff's in their packet, yeah? you with me so far?"

Steve raised an eyebrow. "Uh... yeah. I think so."

"Good. So, Griffindors can be brown, with coffee, tea, bisto etc. Hufflepuffs are yellow, like powdered egg and juice granules. Ravenclaws can be red, like chilli powder. And Slytherin is white, so flour, yeast... and bicarb.

"Now, tell all the people to add their powder to the vinegar and see what happens. Some might be nice, some might just sit there, others might be disgusting. But nobody notices them because a couple of the beakers are filling up with foam and splattering everywhere. So then people only concentrate on that group, waiting to see if it'll happen to anyone else. Do you understand now?"

Bruce took pity on Steve. "It's like the powders are the personality traits that sort us into the houses, and each have positives and negatives, but in Slytherin there's a tiny risk that the traits could cause mental instability or megalomania. Problem is that because of that people ignore the bad things about other houses, like Ravenclaw's focus on schoolwork, or Griffindor's recklessness, and focus only on Slytherin's shortcomings."

Steve's expression cleared. "Oh." He frowned. "But if Slytherin all have the potential to be murderous dark wizards, does that mean they're a little evil?" he asked.

"What?! No!" the Slytherin groaned, dropping his head into his hands.

"What's going on, Tony?" a voice asked. Bruce turned to see a slim, confident ginger girl with a prefect's badge walk over to stand by Tony.

"Pepper!" Tony exclaimed. "Finally! Where have you been?"

"Organising your schedule, Mr Stark," she replied, eyes twinkling. "You're very busy - you did decide to take 18 OWLs, though, so it's your own fault."

Bruce gaped. "18 OWLs... how is that even possible?"

Tony grinned. "I may or may not have access to a timeturner. I'm definitely a genius."

Bruce raised an eyebrow. "But weren't all the timeturners destroyed 9 years ago at the department of mysteries?"

"Hey, genius, remember? I just built a new one, yeah? Easy a pie." Tony bragged.

"How are you not in Ravenclaw?" Bruce wondered aloud.

"Please." he rolled his eyes. "Slytherin has access to all the chemistry equipment I want, we get to live in a dungeon, which is great for bad pick-up lines, and nobody looks at you at all weirdly if you wander around and cackle 'It's alive, It's ALIVE!' at 3 in the morning. Which I actually did once, after fogetting to sleep for 72 hours."

Bruce nodded to himself. "And that's why he's not in Ravenclaw," he stated.

"You didn't answer my question, Tony." She reminded him. "What's the problem?"

"Mr Captain-of-the-quidditch-team, Steve Rogers, has come to the conclusion that as some Slytherins were evil, we all must be evil. And really, throwing aside how you define 'good' and 'evil', that's still blatantly untrue. It's like... like..."

"Mathematical inequalities," she supplied.

Tony stopped, then grinned. "Pepper, I've just remembered why I love you so very very much," he told her. "And it's not just that you occasionally remind me to eat." he pulled her into a gentle kiss.

Bruce raised an eyebrow, ignoring Steve's blushes. After a few seconds he coughed meaningfully and the pair drew apart, eyes twinkling. "Uh... mathematical inequalities?" he prompted.

"Ah, yes! Well, say that this inequality represents Slytherin, yes? You know,  n < x < h  and that sort of thing. Well, say n=6 and h=12, and x is a potential Dark Lord, with a value of say 8. But within that equality are other numbers as well: 4 other integers, for a start, and an infinite number of fractions, all of which aren't evil, but are within the same inequality or House as x. But what you're doing is saying that because x is evil everything within this inequality is evil. See?" Tony finished triumphantly.

"I... think so?" Steve replied.

Bruce rolled his eyes. "Never mind, Steve, I'll explain later." he began to drag him away.

Behind him he heard Tony say teasingly "So, want to come down to my evil lair, Ms Potts? There will be cookies."

"Ah, Mr Stark, but is it your part or my 12%?"

There was a chortle, then "You're never going to let me forget that, are you?"

"Never."

Then all conversation stopped as the couple began kissing again and Bruce hurried away, towing an embarassed steve behind him. Slytherins may not be evil, he decided, but they certainly were crazy.

Maybe he could get to know them a little better?