Harry Potter: INCREDIBLE fan theory reveals plot hole you almost definitely missed

On the Fan Theories board on Reddit, the post by user steampunk_penguin_ has accumulated hundreds of points and has been 92% Upvoted in just a few hours.

The post points out a big problem that all Hogwarts students would have faced, and one that was never seemingly acknowledged all in the books or the films: the cost of parchment.

The theory works out that each student would have needed about 300 sheets per year, not accounting for quills and ink – the cost of which would be gargantuan.

In fact, the theorist claims that “you would need to skin a flock of sheep” to make anywhere near this much.

And given that, say, the Weasley family is quite large (and far from wealthy), it would have been a huge cost.

The writer explains: “Parchment is a type of writing surface made from specially prepared animal skins (any animal will do, but cow and sheep skins were most frequently used).

“To make it, you would subject an animal skin to a multi-step process involving unhairing, flaying, soaking in chemicals, and stretching. As a result, you would get sheets of smooth-ish, rigid-ish (thanks to the collagen in the skin) parchment.

“You might also bleach the parchment to bring it closer to a desired colour, rub it with pumice powder to achieve desired smoothness, or treat it with various kinds of stuff (from lime to eggs) in order to enhance the quality of the final product.

“What I’m trying to get at is that parchment was expensive. Like, really expensive. The manufacturing process was long, complex, and called for ingredients that frequently weren’t exactly cheap.

“People who made parchment required training to master the intricacies of this process (if you messed up, you could render the parchment too brittle to be usable). Of course, parchment makers needed space and equipment (racks, vats, etc.) as well.

“On top of all that, they needed animal skins, and those weren’t exactly cheap either, as breeding and keeping animals costs a lot of money.

“Once you take all this into account, it’s not a surprise that parchment was way more expensive than even the fanciest writing paper today. In fact, it was so expensive that people would go to extraordinary lengths to avoid wasting it.”

Our theorist goes on to show their working in terms of how much paper each pupil would need.

“Homework is usually submitted in essay form. How long are the essays? Snape’s “two rolls of parchment on werewolves” is considered a long essay in The Prisoner of Azkaban, so let’s assume the average length is one roll of parchment. I wouldn’t be surprised if the essays got longer in the final years, but this seems like a safe guess,” they wrote.

“Let’s also assume that not every teacher assigns homework every lesson. If we assume one essay assignment a day, this translates to five a week, and roughly 200 in a schoolyear.

“The students also make notes on parchment. That’s a bit harder to quantify, but even assuming they’re all very economical, this probably adds up to at least another 100 rolls.”

Could the school itself not have supplied students with free parchment? No – our theorist points out that “in the Prisoner of Azkaban Hermione goes to get it herself in Diagon Alley.”

You can read the theory in full on Reddit here, but it’s safe to say that perhaps being a muggle pupil would have been more cost-effective…

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