My successes did not pass McGonagall's gaze. The Professor approached us and carefully examined the products of my magical manipulations.
"Excellent transfiguration, Mr. Granger. Perhaps you have already understood the topic of today's lesson?"
"Gamp's Law with its exceptions, Professor?"
"Precisely."
Standing up and looking around the students closely watching my slightest movement, I declared:
"All material, non-magical, countable, single, and separate objects are subject to Transfiguration or creation from thin air, the change or creation of which does not contradict the laws established by the Ministry of Magic. Regarding exceptions, there are five of them."
"List them?"
"One cannot create food from nothing," I began to bend my fingers, "turn something into a human, turn an ordinary object into a magical one or create something magical. One cannot transfigure money, precious metals, and stones. One cannot transfigure time."
"Excellent," McGonagall nodded. "But here is an important question for you, and everyone else. How do you understand this law with its exceptions?"
McGonagall looked around the class—everyone looked thoughtful.
"It seems to me you are old enough to move from simple rote memorization to meaningful understanding. At least regarding basic material. Anyone want to answer? Mr. Granger?"
I hadn't sat down yet, so I decided to express a few conclusions and assumptions based on both read material and a certain abstract and far from complete, but still understanding of the essence of such transformations from memory shards.
"I cannot speak for sure and assert something, but I have some thoughts regarding this topic."
McGonagall nodded approvingly, as if giving permission to continue.
"The law itself has a certain duality. It states that some types of transfiguration are simply impossible to carry out, and also that some of those that are possible are punishable by Ministry law."
"Continue, Mr. Granger," the Professor nodded.
"The object of transfiguration must satisfy several conditions. It must be singular, be an independent numerical unit, not be in a rigid immobile coupling with other objects excluding their mutual mobility, and most importantly—must not possess magical properties."
"Quite a competent explanation, Mr. Granger," the Professor nodded again. "I recommend those who are unable to decipher the essence of the law for themselves to definitely write down these words. Mr. Granger, I would like to hear examples of objects satisfying one or several requirements."
Quite a large number of students from our year immediately rustled quills on parchment.
"I think, Professor, everything is simple with a non-magical object—everything that does not possess magic, a magical property, is not enchanted, does not possess activated runic engraving, and things like that. Countable—that which can be mentally and factually separated from the community of similar objects. For example…"
I took my ordinary notebook from the table.
"A notebook. One piece. Separable from the community of other notebooks. It can be transfigured. However, one cannot transfigure a part of the notebook, positioning the transfigurative impact precisely on a part of the notebook. But one can transfigure a separately selected sheet or several sheets."
"Several sheets? Shouldn't the object be single and separate?" the Professor smirked, and some students looked at me mockingly.
"Depends on the type of manipulation. Technically, one spell needs one object, and one spell won't work on several objects. However…" I held a dramatic pause, and the Professor seemed to understand what I was getting at and was a little surprised. "One can use the Meyer-Turner formula to combine several spells and objects of their application into one cascade transfiguration spell. Purely practically, you get one spell for several objects. A little trick."
"Magnificent. Seventh-year material. I see you read additional literature, and, what is important, understood it," McGonagall's smile became much more obvious. "What about the other requirements?"
"With a separate object, everything is simple. You won't be able to transfigure, for example, a nail firmly driven into a wall. But a nail that wobbles inside it—no problem. Should I state the understanding of exceptions?"
"Of course, Mr. Granger. I, and I dare hope, the others, are extremely interested in your conclusions."
A couple of students snorted dismissively, but under McGonagall's formidable gaze immediately assumed the appearance of diligent students attentively listening to a colleague.
"Well then… One cannot create food from nothing. An old formulation, in my opinion, not quite correctly revealing the essence. The object of transfiguration cannot be 'nothing' in principle."
And yes, I perfectly know that matter is a form of energy, which means absolutely everything can be transfigured into anything. But in local realities, there is no justification for this, and the depth of knowledge of the universe in both the ordinary and magical worlds is far inferior to the elven one. Simply put, there is no point in talking about this, as well as proving it in practice.
"Regarding food, I think I know what the problem is. Food is an object with an extremely complex structure, and its creation requires extremely deep knowledge in the theory of the structure of matter and space, along with knowledge about the functioning of the organism as a whole, and metabolism in particular. Transfiguration, I emphasize, specifically transfiguration of food that would fully perform the function of this very food—is a colossally costly business both magically and mentally. But there is another problem."
I tore out two sheets and with a wave of the wand turned them into glass cups one by one.
"Aguamenti," I pronounced the spell, filling one cup with water, and repeated the maneuver with the second.
"The second problem is the duration of transfiguration."
For clarity, I turned the water in the cups into two apples. And no, they are not real.
"Not food, of course. Similar in structure," I cooled the ardor of several students who began to whisper excitedly.
"By my estimates, magic is invested for five minutes of transfiguration. What do you think, Professor, am I not mistaken?"
McGonagall waved her wand over one apple with an important look, and then over the second, after which she nodded, confirming my own sensations. It seems I really found the necessary key for transfiguration—now this discipline is not a problem for me. I took one apple in my hand.
"So. Time of transfiguration. Drawing conclusions from various material on the subject, I came to an unambiguous and disappointing conclusion. If you divide the result of transfiguration in two, then the duration of transfiguration will be halved. This is connected, it seems to me, with the fact that the spell sort of divides between objects, dividing the invested magic as well. And as we know, not the size or density of the object and the target of transfiguration affects magic costs, but their structural complexity. And if you divide into many parts?"
I forcefully slammed the apple on the table, shattering it into a huge number of particles. The smallest almost immediately turned into water, others, larger, held on for a couple of moments longer, and so on until five largest pieces remained among the puddle of water. Just as I wanted to speak, the smallest of the remaining turned into water.
"Needless to say what could happen if you transfigure this apple from a chair, or a table, and start consuming it."
"A very harsh example," the Professor nodded, removing traces of my demonstration with a wave of the wand. "Did the other exceptions yield to your extraordinary mind?"
"Undoubtedly, Professor," I nodded with a slight smile, causing gnashing of teeth from some of the students. "One cannot turn anything into a human. Everything is simple here. Just as any transfigured creature will not be alive, but only a golem, so it is with a human. Purely theoretically, as with the apple, one can recreate a body with unimaginable costs, but a human is not just a body, but also a soul. That's where the problems are."
"That, Mr. Granger, is already sections of Dark Magic," the Professor spoke sternly. "I strongly recommend not practicing them, and it is far from a matter of legality."
"I know, Professor, just stating a fact. That which we all understand as a human is indeed impossible to transfigure. Regarding turning something into a magical object or creating something magical—here, unfortunately, I do not fully understand the reasons for the failure. I assume one can enchant a transfigured object, and then fixed with a permanent transfiguration formula. I think the point is that transfiguration is the science of transformations of material objects. Magic and charms are immaterial."
"Correct, Mr. Granger."
"Money… Hmm," I pondered. "Depends on which. Ordinary people's money is made of ordinary materials, and they can successfully be transfigured theoretically, but such things, if I remember heard conversations correctly, are closely monitored by the DMLE."
"You touched upon a very important point," McGonagall nodded and addressed everyone. "This exception appeared at the end of the seventeenth century. In those times, both Muggles and wizards used money made of precious metals and their alloys. That is why their transfiguration is not considered possible. By the way, Mr. Granger, what is the reason for the impossibility of transfiguring precious metals and stones?"
"Magic dispersion," I shrugged.
Now the whole class was diligently writing down, albeit reluctantly.
"More details?" the Professor asked.
"Gold, platinum, and pure silver possess unique properties that do not allow any magic to anchor on them. Again theoretically, when we try to transfigure an object into gold, transfiguration almost succeeds—at the moment when the object becomes gold, it immediately sheds magic, returning to the original. This moment is completely elusive in time, therefore the impression is created that transfiguration fails."
Neither I nor Professor McGonagall could help but notice Hermione's raised hand.
"Miss Granger?" the Professor immediately addressed her.
"I would like to add and correct. Silver successfully undergoes transfiguration."
"By no means," I shook my head, causing displeasure from Hermione, red-haired Weasley, and Potter. "You mean low-grade silver, eight hundred, eight hundred thirty, and so on. They have extremely low cost, low magical value due to high impurity content, and transfiguration in them succeeds precisely due to the low silver content. But even so, such silver content negatively affects the duration of transfiguration."
"One can use a transfiguration fixing formula, obtaining an alloy with a small silver content," Hermione parried.
"Magic costs are too high, and such an object loses all its value. Creating even a small volume of such an alloy will exhaust a wizard incredibly. Giving it the shape of jewelry makes no sense due to the low cost of such an alloy, and in the end, it will be suitable only for remelting, purification. And that is costs again. Much more effectively one can earn money simply by getting the most worthless part-time job. The same applies to gold, only magic dispersion in gold is many times higher than silver, and getting even five hundred twenty-fifth purity is practically impossible."
"I don't understand anything, what language is he even speaking?" complained redhead Weasley, causing chuckles from the guys, and a mixture of embarrassment and indignation for a friend from Hermione.
McGonagall's stern gaze calmed the fits of fun in the class.
"Precious stones?"
"They are magical objects at all, albeit to an incredibly insignificant degree. Attempting transfiguration leads only to turning into carbon, quartz, and other dust, from which transfiguration immediately falls off, and the initial object also turns into dust."
"Time?" the Professor asked shortly.
"Time is not a material object. It is, rather, a subjective perception of the rate of change of the state of matter. It has absolutely no relation to transfiguration, for that matter."
"Simply magnificent, Mr. Granger," McGonagall smiled joyfully, and even somehow girlishly clapped her hands neatly. "Twenty, no, thirty points to Hufflepuff. Mr. Granger…"
"Yes?"
"I think I can give you credit for all the covered material. You coped with the practical part, and your understanding of the covered basics of transfiguration raises no doubts."
"Thank you, Professor."
The remains of the lesson passed somewhat detachedly—we practiced another transfiguration according to the program for everyone, but the first for me. Nothing special.
After Transfiguration, we, again with the whole crowd of third-years, headed to the DADA classroom.
"Now absolutely everything together," Justin shook his head sadly, wedging himself between me and Ernie. "And I got so used to studying either only with Ravens or Griffs."
"Well, I don't know," I shrugged. "I like everything as it is."
Inadvertently I glanced towards Malfoy and his comrades. It was funny to see how he importantly tells something, two dummies portray golems simply moving nearby, a brown-haired guy unknown to me so far listens to him neutrally, a quite cute brunette with a bob nods and agrees, sometimes inserting a couple of phrases. It was amusing how this brunette chooses words and time for statements. An experienced elf smells a whiff of intrigue and opinion manipulation, but that is an elf—a teenager would perceive everything at face value. Especially such a proud one as Malfoy.
On the other hand, I noted Hermione and her friends too. Redhead Weasley was saying something, like, she is the smartest anyway, Potter nodded, and Hermione herself was digging in the timetable.
"Good that classes are now together for everyone," her phrase reached me.
"Classes?" Weasley didn't understand. "I talk to her about one thing, and she talks about classes."
"Why?" Potter didn't support his friend's indignation.
"The schedule shifted slightly, and I can attend all additional classes without haste."
"Ooh, it's all clear," the redhead waved it off.