Harry Potter and the Hermetic Arts
Chapter 20: The Hermetic Method
As Harry had expected, Hermione came into the library in search of him first thing the following morning, going so far as to skip breakfast; it had been for this prediction that he had decided to do his morning independent study in the library rather than in his dormitory room.
She came straight to the table where he was working, opening her mouth to speak, but he silenced her by holding up a finger before jerking his thumb towards the sign behind the ever-present Madam Pince. The bushy-haired brunette frowned, and Harry slipped the sheaf of paper he was writing on into the geography workbook he was working from, then closed it and put it into his haversack, quickly pocketing his writing implements before standing up and pushing the chair in under the desk.
Instantly, the girl seized his free hand, pulling him after her as she rushed out of the library; behind her desk, Madam Pince quirked an eyebrow, but otherwise chalked the behavior of the girl who clearly loved the library up to young love. She had no idea how wrong she was.
Hermione lead Harry through the just-filling hallway, up a flight of stairs, through another hallway, and then up another staircase before finally yanking him into an abandoned classroom and securing the door behind them.
"How did you do it?" she asked.
"Do what?" Harry asked back, playing dumb.
"Last night," Hermione said. "You say you can't do magic, but you did magic last night. Not just magic, either, but wandless magic."
"I never said I couldn't use magic," said Harry. "I always said I couldn't get the spells we were being taught here to work for me."
"Well, you let me assume you couldn't use it," said the girl. "And that's not very nice."
"I let a lot of people assume all kinds of things about me," Harry retorted tightly. "It's called 'information control'; by managing the information people receive about me, I can control how they see me and, to a lesser extent, how they feel about me.
"Take, for example, the professors. McGonagall pities me because she thinks I can't use magic; even though she doesn't say anything, you can see it in the way she looks at me, like I'm somehow less than everybody else. The wee pensioner who teaches Charms…"
"Professor Flitwick," Hermione interrupted, feeling slightly offended by Harry's description of her favorite professor.
"Yeah, sure," said Harry, shrugging. "He compares me to somebody else in his head every time he looks at me and knows I can't cast a charm to save my life; to him, I'm a disappointment.
"Then, there's the students. Hufflepuffs think they can help me overcome my difficulties with hard work alone, if I'd just let them. Ravenclaws think I'd make for a great subject for an experiment. Gryffindors love to speculate whether I used up all my magic defeating He-Who-Must-Not-Be-Named. And Slytherins think I'm not even worth bothering about because I'll never be a threat.
"Except Malfoy. He thinks I'm He-Who-Shall-Not-Be-Named, biding my time until I'm powerful enough to once again take over the world. Wonder who gave him that idea."
Hermione considered what Harry was telling her. While she could not vouch for his observations about the professors, as she had never thought to watch them in such a way, she did know the way students had speculated about her friend since school had begun two months ago and it was discovered Harry Potter was hopeless with a wand in his hand, and that Malfoy had stopped harassing him ever since the incident during the second week of the semester.
"But why would you want people thinking you can't use magic?" Hermione asked.
"Because I want to be underestimated," said Harry. "I want people to look at me and think to themselves, 'Harry Potter can't possibly do anything to me magically.'."
"But why?"
"A magical bogeyman came to murder me when I was a toddler. They say I defeated him, but they never found a body, and I've read enough comic books and watched enough movies to know that means he's probably not really dead yet."
There was a moment of silence as Hermione considered what Harry told her, but then she pushed it back aside as her curiosity got the better of her. "How did you do it?"
"Do what? You'll need to be more specific."
"Wandless magic! Only wizards and witches of great skill use it reliably!"
"Swear you won't tell anyone about any of this?"
"I, Hermione Jean Granger, swear I will not tell anyone about any of this."
Wordlessly, Harry dragged the lectern over to the door, lodging it under the handle and barricading the door shut before turning back towards Hermione.
"It's not a form of wand magic," he said.
"Huh?"
"The magic I used wasn't wand magic that I then took the wand out of," Harry explained. "Wands were never involved with it in the first place."
"But that's impossible," Hermione protested. "Magic can't be done without wands unless you're one of the most powerful and disciplined…"
"I've been doing it since I was nine," Harry interrupted, interrupting Hermione.
"But that's not possible!"
"What did I tell you about believing what other people tell you?"
"That I should ask why they would tell me those things?"
"Now, why would they tell you it's absolutely necessary to have a wand for magic?"
"So they can sell more wands?"
"And?"
"If they take away our wands, we believe we won't be able to use magic?"
"And?"
"We'll be afraid they'll take away our wands, so we won't do things that'll make them take away our wands?"
Harry let the silence hang in the air for a moment before he continued.
"What I do, if I were to give it a name, would be the Hermetic arts, using the Hermetic method," he explained.
"Hermetic arts? Hermetic method?" Hermione asked.
"C'mere," said Harry, beckoning Hermione to approach as he took off his haversack, setting it on the floor of the otherwise abandoned classroom. When she got within arm's reach, he suddenly grabbed her by the wrist, dragging her along as he dropped into his haversack.
With a shriek, the bushy-haired girl fell onto the tousled-haired boy, gingerly opening her eyes when the fall proved much shorter than she expected. Sitting up, she looked around in awe as the lift slowly descending into the haversack's depths.
"You have so many books," Hermione said in awe, eyes darting from side to side as she took in the sight before her. "How…?"
"Flourish and Blotts got me about a hundred," Harry said. "The rest are from just raiding bookstores whenever and wherever I found them."
"I wish I had this many books," the girl said wistfully, eyes wandering the private library while she followed Harry through the stacks, eyes drifting over the numbers hand-printed on labels stuck on the bottom of the spine of each book. "How is this organized?"
"Dewey Decimal," Harry said shortly as he stopped at 793.93 and started pulling books off the shelves, shoving them into Hermione's arms without asking first. She took them without protest, although her brow furrowed as she saw the titles: Advanced Dungeons & Dragons 2nd Edition Player's Handbook, Ars Magica: The Art of Magic, and Shadowrun: Where Man Meets Magic and Machine.
"These are games," she observed.
"And the basis of my magic," Harry said, leading her back to the lift out of the bag.
It took the two a few moments to get settled back in the classroom; as Hermione tried to get comfortable, Harry was going through Shadowrun: Where Man Meets Magic and Machine, seeming to be in search of something, brow furrowed in concentration.
Finally, he came to a stop, setting the book on the desk between them and turning it around so she could read more easily. "Read the left-hand column on the page on the left," he instructed.
Hermione did as she was told, the frown on her face deepening the further down the page she went; by the time she finished, she was practically scowling.
"This is a game," she reiterated.
"What works, works," Harry said with a shrug. "But as it says, Hermetic magic is scientific; you have to do research, design spells and actually work out how things function."
"That doesn't make it not a game!" Hermione protested.
The noirette sighed, his right hand rising from his side until it was in line with his collar bones, fingers pointed skyward and palm tilted slightly towards the girl, he then extended his left hand so it faced Hermione, who instinctively ducked as he said, "Creo vim."
Instantly, a translucent green disc formed in thin air in front of his outstretched hand; it was the size of an extra large pizza and similarly shaped, and as Harry moved his hand, it followed, always staying in front of his open palm.
"What is that?" asked Hermione after a moment, only a little bit certain it wouldn't hurt her.
"Shield, a basic defensive spell," Harry said. "Come on, throw things at me."
Hesitantly, she picked up a pencil and tossed it lightly at the boy, who moved his hand so that the shield intercepted the projectile. She followed up with an eraser, and then another pencil, and Harry blocked those as well.
"All right, I believe you," said the girl, having run out of things to throw. She watched as the boy's brow furrowed before the disk blinked out of existence.
"How does it work?" Hermione asked.
Harry picked up Ars Magica: The Art of Magic, quickly paging through the book until he found what he was looking for before putting it down in front of the girl. "In my experience, Hermetic magic has a lot components: Forms and Techniques make up the verbal components, gestures make up the somatic components, some spells require the use of material components to make them function properly, and then there's visualization of the effect and the channeling of Astral power that gives the spell its actual energy source."
"Astral power?" asked Hermione, dumbfounded by the assertion. "There's no such thing as the astral plane."
"And yet, somehow, I can draw power from the Astral Plane and cast spells with it," Harry said. "Listen, I know I've been telling you to be skeptical, to question everything, but there's a flip side to that too: reality doesn't care whether you believe in it any more than you care whether reality believes in you. You're real, reality's real; neither of you are fairies who need to be healed."
Hermione tried to grasp this idea, the need to be skeptical of everything even when questioning things wouldn't alter them; it was something she couldn't comprehend, not even after several silent minutes of trying to figure out what it meant, and finally, she gave up, her shoulders slumping as she felt defeat wash over her. "I don't understand," she admitted.
"Questioning reality doesn't change reality; rather, it changes your perception of reality," Harry explained, only to draw a blank look from the girl. "There's facts, and there's truth. Facts are objective, immutable, what reality is based on; truth is subjective and dependent on individual experiences. What you may view as truth isn't necessarily the facts, because the truth is different between each individual person."
"I don't get it."
"Here's an example, then," said the boy after a moment. "Up until not too long ago, you believed the truth was only the most powerful and disciplined witches and wizards can use magic without a wand; then, I showed you it wasn't the case, and now, your truth is that, you don't need to be powerful and disciplined to use magic without a wand. However, regardless of what you believed…"
"It was always possible to use magic without a wand," Hermione finished, finally understanding. "So, a fact would be 'diamonds are valuable because they're rare', but the truth would be, 'diamonds are valuable because they're a girl's best friend'."
"Actually, diamonds are basically worthless," Harry said, and Hermione frowned. "The reason diamonds are considered valuable is a psychological phenomenon created by advertisers; they're actually very commonly found, and if you took a diamond to a jeweler, they wouldn't buy it from you unless it was a remarkable specimen. Diamond cartels actually have more diamonds than they know what to do with; they're just limiting supply so they can keep their profits high."
"Fine," huffed Hermione. "A fact would be, 'gold is valuable', but the truth would be, 'gold is valuable because it's shiny' or 'gold is valuable because it's rare'."
"Yes, that's correct, although, if you're going to try to find a truth about the value of gold, you might want to make it, 'gold is dense, soft, shiny, malleable and ductile, has the highest corrosion resistance amongst all metals, is a very good conductor of heat and electricity, and will not oxidize, which makes it a very useful and desirable metal for industrial applications; because there are so many uses for the material, which is also incredibly rare but also very pretty, gold is extremely valuable'."
"Huh," said Hermione, brow furrowing as she digested this new information. "How do you know this? And why?"
"I asked Romy," Harry said. "She's working on her doctorate in chemistry, so she knows a lot about material sciences, and after I asked her, I cross-referenced with books and my own experiences in the world, like how high fidelity sound systems use gold to improve audio quality or dentists fit gold crowns over cavities."
"Oh."
"Yeah. So anyways, how the Hermetic method works is like this: when I create a new spell, I have to decide what exactly it does, then figure out the Form and Technique that would apply to it. From there, I have to infer what gestures would represent what I'm trying to do, as well as figure out how to visualize the process of the spell at work. After I've got all that down, I practice it again and again, at first without applying any Astral power at all until I can perfectly perform the incantation and the gestures smoothly while at the same time completing the visualization without a mistake; then, I try the spell with Astral power, but only the minimum amount of it I can channel, in case something goes wrong with the spell. Once I'm certain the spell will behave the way I want it to, then I can work on the amount of Astral energy I use during any single casting, until I find a balance between power and not being worn out by the casting. After that, I repeat it until it's practically muscle memory.
"And that's only for rote magic."
"Rote magic?" Hermione asked, once again confused.
"Oh, right," Harry said. "There's actually two kinds of magic within the Hermetic arts: rote magic and spontaneous magic. Rote magic are spells you can use again and again to achieve the same or similar results every time; it's actually not unlike magic with a wand, where if you say the right words and use the correct gestures, you're guaranteed to get practically the same result each time you cast a spell. Spontaneous magic is for one-time effects, things you can't necessarily duplicate in the future because it has too many moving parts, where the situation might not be the same the next time or when you have to create a new magical effect on the fly."
"You can do that?" asked the girl, eyes widening at the idea.
"Would it matter if I couldn't?" Harry asked.
"No," Hermione admitted. "If you told me you could but you couldn't, then all that would do is change my truth, not the facts."
"That's right," Harry said, nodding. "Don't ever believe something just because somebody tells you it, not even if it's me."
"Then who can I trust?" Hermione asked, eyes narrowing. "Why can't you just tell me the truth?" Then, realizing the answer, she interrupted Harry before he could speak. "Information control."
A moment of quiet followed as Hermione fumed silently to herself. Then, she stood so she was eye level with Harry, locking her rich chestnut brown eyes with his piercing emerald green ones as she walked him down; when he stood his ground, which she did not expect, the girl found herself standing awkwardly nose-to-nose with her friend, but she was already committed to it, so she could not just change it.
"Do you trust me?" she asked.
"I do," he said.
"Then swear you'll never lie to me," Hermione demanded, trying to keep her voice even.
"I can't do that," Harry answered back calmly. "There'll always be things I can't tell you, because some wizards can read minds, and not telling you something would be a lie of omission."
"Then swear you'll always tell me the truth, as much as you can and as you best understand it."
"I swear I'll always tell you the truth as I best understand it when you ask me for it, with the caveat I may not always tell you the whole truth," Harry swore, staring the girl dead in the eye as he did so. "Further, I swear, if you ever ask me a question I cannot answer truthfully or I think the answer will hurt you, I'll ask you not to make me lie to you."
"I can live with that," Hermione said softly. Before she could step back, however, Harry had his hands on her shoulders.
"I need you to swear you'll always keep my secrets," Harry said.
"I swear, I'll always keep your secrets," Hermione said seriously, without hesitating.
There was a moment of silence as Harry continued to hold Hermione by the shoulders. Then, with a smile on his lips, he said, "If people who didn't know us saw us, they'd think we're about to kiss."
Flustered, Hermione stepped backwards, blood rushing to her cheeks. Seeing the smile on her friend's face, she realized he was simply teasing her.
"Will you teach me the Hermetic method?" Hermione asked.
"If we do this, you'll need to know what you're getting into," Harry said, and Hermione nodded. "There'll be times I will have to hurt you, and you will have to find it in your heart to forgive me. Can you do that?"
"I can," said the girl without thinking.
"Shake?" Harry asked, extending his left hand.
Hermione took Harry's hand in her own, clasping it firmly as they shook.
A shriek of agony forced its way past her lips as a sudden jolt of searing pain shot through her hand. Looking down, Hermione saw in horror the blade of slender knife stuck into the back of her hand and out of the back of Harry's.
"Harry… there's a knife…"
"I know," said the boy calmly as blood dripped from their hands. "I put it there."
"What?" gasped Hermione, starting to hyperventilate and get cold sweats. "Why?"
She watched in shock as the boy calmly pulled the blade out of her hand, feeling a detached kick of agony as the metal left her flesh, and she pulled her hand out of the boy's, clutching wound as her hand throbbed in excruciating pain.
"This is something that may save your life one day, so pay attention," said the boy, tossing the bloodied knife onto the desk between them. Making sure the girl was looking at him, he held up both hands, index and middle fingers pointing up together and thumbs pressed against his curled ring and little fingers, then brought them down to waist level, saying, "This is the prana mudra, the life force seal; as the name implies, it governs life forces. The Technique for this spell is 'creo', Latin for 'I create', and the Form is 'corporem', 'body'. Watch your hand; it'll give you the visualization you need for this spell."
Hermione watched as the boy's brow furrowed in concentration as he said, "Creo corporem," in a calm, even tone, even as blood pooled on the floor under him. She felt a warmth penetrate her open wound from the outside and felt an intense itching sensation that made her want to reach into the injury and scratch the inside; looking down at her hand, she watched in a combination of shock and amazement as the cut pulled together and knitted close, healing until there was nothing left besides a small, pale scar no more than a centimeter long on the back of her blood-caked hand and the memory of the agony of being stabbed.
"Why did you do that?" Hermione asked.
"I did warn you beforehand, and you said you understood," the boy said, before holding up his own hand, which was still leaking blood. "Would you be so kind as to heal me?"
In an instant, the memory of her experience flashed involuntarily before her eyes; in it, she could recall with perfect clarity the gesture he had used, the words he had said, and the image of her own wound closing. Instinctively, she mimicked them, performing the prana mudra as she said, "Creo corporem?", the image of her closing wound still vivid in her mind.
"It should be a statement, not a question," the boy instructed. "Don't forget to channel Astral power when you're casting. And focus on the injury you want to heal."
"I don't know how to channel Astral power," Hermione protested.
The boy sighed and walked up to her, then reached over, pressing his right hand against her forehead. Shocked, Hermione found herself standing still, but then felt something warm flow from the boy's hand into her head, down her back and into every nerve, making them tingle and suddenly feel like they were on all alive at once. "Feel that? That's Astral power. Now, instead of me feeding it to you, try drawing it out of the world."
"I don't know how, though," Hermione reiterated.
The boy shrugged. "I can't really explain it. Just try it," he said. "Remember the sensation of Astral power flowing through you, and try to pull it out of the air."
Hermione frowned at the non-explanation, then sighed; Harry had been very clear on explaining everything else, so she decided the vague explanation was him not having a concrete idea of how he managed it himself. She still had no idea how the astral plane worked, but she did have experience with magic using a wand.
Closing her eyes, Hermione focused on the warmth she had felt in her tummy every time she cast a spell with a wand. Feeling it stir, she tried to shape it and found it malleable and willing to bend to her will, and so, she pulled on it, drawing a small bit through her body, and her nerves came to life in the same way they had when Harry had injected Astral energy into her body. Closing her eyes, she focused again on the words Harry had spoken, the gesture he had made, the memory he had told her to remember; then, opening her eyes, she started intently at his bleeding hand, mimicking his previous gestures and saying, "Creo corporem" as she focused on taking the energy from within her that she had drawn on to healing her friend's open wound.
Suddenly, the warmth rushed out of her in a wild wave, and her eyes widened in shock as Harry's hand healed in an instant; yet, the warmth flowing forth beyond her control with no signs of stopping. She felt something something start to run out of her nose, and she saw Harry's expression quickly become one of concern as he interlocked the fingers of his right hand with those of his bloodstained left in the direction of his palms, index fingers raised and pressed together with his thumbs, exclaiming, 'Creo auram!"
Hermione wobbled as her vision started to blur and she felt light-headed, barely able to make out the electricity crackling along the surface of her friend's hand as he reached to grab her; the instant his skin touched her own, she felt a searing pain rip through her entire body, and she went completely rigid, her muscles locking up tight as her friend eased her to the floor. However, the warmth suddenly stopped flowing from her tummy, as though a door had slammed shut, and her vision cleared slowly, leaving her to look up from her back at the boy who was supposed to be her friend.
"What was that for?" she asked, her breath ragged. "It really hurt."
"You nearly died," said the boy, wiping her nose a piece of tissue paper before showing it to her.
Hermione stared at the blood on the tissue. "What happened?"
"You channeled too much Astral power, and it damaged you physically," the boy said.
"I didn't use that," the girl confessed. "I used the magic that get used with the magic they teach here."
"Whatever you used, it nearly killed you," Harry said. "You lack the precision control necessary to close the channel once you achieved what you wanted to. That'll come with practice."
"What did you do to me?" Hermione asked, still unsure what had transpired.
"I shocked you when I kept feeling magic flow into me even after the wound had closed and you started bleeding; it was the only way I knew how to shut down the flow of magic, by making every muscle in your body lock up and forcing an electric current through your nervous system, which is how magic is channeled."
Hermione let the information sink in for a moment, then said softly, in an accusatory tone, "You didn't have to stab me."
"I kind of did," Harry said.
"I don't believe you."
"I swore I'd always tell you the truth."
"Then why did you have to stab me?"
"The spell I was teaching, Heal Wounds, is something you'll one day be casting on yourself when you're in a lot of pain because you're very badly hurt," the boy explained. "I once had to cast it on myself while I had cracked ribs and a broken jaw. Not to mention, studies have shown memories formed during traumatic events remain seared into the victim's mind for a very long time, which is one of the reasons people who have had traumatic experiences can't stop reliving them, and this is a spell you'll want seared into your memories, because when shit goes to hell and you're seriously injured, you don't want to forget how to heal yourself."
"You stabbed me for my own good?" Hermione asked, still skeptical.
"You don't believe me?" asked the boy, cocking his head to the side.
"I believe you. I just think there might have been a better way."
"There might have been, but I couldn't think of it in the moment. I'm sorry I hurt you like that."
"I forgive you, Harry," Hermione said, before looking around. "How're we going to clean up all of this blood?"
Hermione watched Harry look around, taking in all of the blood, then clasp both hands together, index fingers extended together and the rest intertwined against the back of his hands.
"Perdo corporem."
As she watched, the pools of blood started to shrink in on themselves, until not a single drop remained on the floor, table, knife or even their skin.
"What spell was that?" Hermione asked. "I know 'corporem' is 'body', so that's the Form, but what's 'perdo'?"
"This actually isn't a spell," Harry said. "I used spontaneous magic to destroy all the blood. 'Perdo' is 'I destroy'."
"Why did you have to use spontaneous magic? Couldn't you have used rote magic?"
"I could have, if I knew a spell with the application," Harry explained. "I never researched or developed a spell for cleaning blood, so I have to create the magical effect on the fly."
"Oh," said Hermione. After a moment, she changed the subject. "Where do the gestures you use come from?"
Harry chuckled to himself. "I actually first saw magical gestures in comic books," he admitted. "Doctor Strange and Doctor Fate both used specific gestures when they cast spells, so I took the comics to a librarian, who helped me figure out they were mudras, ritual gestures use in Buddhism, Hinduism, Jainism and yoga; there are some Japanese kuji-in thrown in as well, but I rarely need to use those. From there, I did research on all of those and learned as many mudras and their meanings as I could; only then could I use them in my magic."
Hermione cocked her head to the side as she looked Harry in the eyes. "You're telling me your magic is based entirely on comics and games?" she asked, not wanting to believe what she had just been told.
"Well, a lot of research and development went into it, but the short version answer is 'yes'."
"I don't know what to say," said the girl, as she plopped down into a chair, still trying to process this sudden revelation on just what magic was to her friend.
"Well, I do," said the boy, as he picked up one of the books and dropped it into her lap. "You're going to have to do a lot of research to develop your own spells, so you should learn these Forms and Techniques first before you start on anything else."
Hermione looked down at the book in her lap, then picked it up. Even though she was a little disappointed to learn just where Harry's magic came from, she decided it didn't matter; at the end of the day, it was still magic, even if it was a little unusual in its origin.
"Once you learn these Forms and Techniques, then I'll start teaching you the gestures I use. In the meantime, I want you to keep practicing manipulating whatever magical force you use whenever you have time, until you can turn it on and cut it off at will; if you can't control how much magic you're putting into a spell, it'll be dangerous for you to use any magic at all.
"Honestly, given how much you like to do read and research, I think the Hermetic method is really right up your alley," Harry added. "You'll be great at it once you learn all the basics."
"I hope so," Hermione said absent-mindedly. Already, her focus was on memorizing the Forms and Techniques like Harry was instructing her to, and she was going to learn this as fast as she could so she could start learning spells soon.
Author's Notes: Roll credits... (TM)
Harry's indifference towards magic involving wands stems from his lack of interest in its practical applications; for him, wand magic is only for passing classes, and he can use the Hermetic arts everywhere else, so he sees no purpose in learning a more restrictive form of magic besides it being a requirement for school. It's for this reason he hasn't really done that much research into the nature of wands and why magical society seems to be so obsessed with them, because his focus on wand magic has been primarily in trying to get it to work for himself, which certainly explains why he doesn't know about traces on wands.
Yes, there's a method to the madness, but, given the cyberpunk-influenced aesthetic of the storytelling, I felt it wouldn't be appropriate to give it away until the narrative itself gave Harry cause to do so. It's one of the things I've always loved about good cyberpunk fiction: stories start where they start and don't give the readers background until there's a reason for the exposition to be revealed within the context of the story and its characters, while characters also don't just talk about things they already know about just for the convenience of an audience they wouldn't even know exist, which I feel reflects more closely to my experience with how life is than the more traditional narrative structure that begins with the origin story and lays out everything from the start.
The division between rote magic and spontaneous magic mirrors the division between wizards and sorcerers in Dungeons & Dragons; European magical society also relies almost entirely on rote magic, so the idea of spontaneous magic in the way Harry uses it is probably foreign to them. Ars Magica clearly delineates between the two types of magic as well, though the book never calls the system of fixed spells "rote", yet the term is used in both Mage: The Ascension and The Dresden Files Roleplaying Game, but the former won't be published until 1993, and the latter in 2010.
Heal Wounds comes from Shadowrun; while arcane spellcasters do not get healing spells in Dungeons & Dragons, leaving the treatment of illness and injury in the domain of clerics, Shadowrun has no such reservations. It's another reason why Harry derives his magical system from a hodgepodge of sources; by mixing so many sources together, he has access to so much more than just what one system might offer him, and some of it is what he needed to survive his life.
Harrying referencing the books comes from my own referencing the books to find the correct sections he would need be directing Hermione to. I've always believed those little details make a story, even if I'm the only person doing the work and nobody really understands how accurate to life the details are.
Credit to Shinshikaizer for the original story pitch and goalie12345 for copy-editing. Furthermore, my thanks to Romantically Distant for additional editing and proofing.