Inspired by  I was wondering why the Half Blood Prince left his book as a class copy. One would think that it was precious to him, since he invested so much in it. He made up potions and spells up by his own. I would expect him to keep it to himself. Both, because of the personal value of it, and to prevent others to (as happened at last) use his work (misguided and/or against him).  Is there any canon explanation why his book was left as class copy?
123898
Advanced Potion-Making (by Libatius Borage!) was used for sixth year Potions classes. Canon does not make clear whether it was also used for seventh year Potions, so I'm going to presume it was only the sixth years' textbook. Slughorn passes out two battered copies of Advanced Potion-Making to Harry and Ron, and Harry ends up with Snape's old textbook, as we know. A few relevant passages from Half-Blood Prince and Deathly Hallows:     Harry bent low to retrieve the book and, as he did so, he saw something scribbled along   the bottom of the back cover in the same small, cramped handwriting as the instructions that had won him his bottle of Felix Felicis, now safely hidden inside a pair of socks in his trunk upstairs.   This Book is the Property of the Half-Blood Prince   Half-Blood Prince - page 183 - Bloomsbury - chapter nine, The Half-Blood Prince   ‘SECTUMSEMPRA!’ bellowed Harry from the floor, waving his wand wildly.   Blood spurted from Malfoy’s face and chest as though he had been slashed with an invisible sword. He staggered backwards and collapsed on to the waterlogged floor with a great splash, his wand falling from his limp right hand.   Half-Blood Prince - page 489 - Bloomsbury - chapter twenty-four, Sectumsempra   ‘You dare use my own spells against me, Potter? It was I who invented them – I, the Half-Blood Prince! And you’d turn my inventions on me, like your filthy father, would you? I   don’t think so ... no!’   Half-Blood Prince - page 563 - Bloomsbury - chapter twenty-eight, The Flight of the Prince   ‘Snape?’ shouted Harry. ‘You didn’t say –’   ‘He lost his hood during the chase. Sectumsempra was always a speciality of Snape’s. I wish I could say I’d paid him back in kind, but it was all I could do to keep George on the broom after he was injured, he was losing so much blood.’   Deathly Hallows - page 66 - Bloomsbury - chapter five, Fallen Warrior   There is no question Snape is the Half-Blood Prince, or that Harry got hold of Snape's former textbook; as well as useful potion-making information, it also contained rather questionable (Levicorpus) and downright dangerous original spells (Sectumsempra).  Not only did Snape have the opportunity to secure his copy of Advanced Potions Making at the end of his sixth year, I'm guessing he had all of his seventh year to destroy, hide, or keep the book as well. Also, he had at least five years as Hogwarts' known Potions master to ensure the book was kept away from the students.   As Potions master, Snape would have had access to all inventory relating to the Potions classes, including Hogwarts' copies of any potions textbooks. It would seem likely, while arranging or cleaning his classroom and stores, Snape would have come across his old textbook at some point. I personally think he would've recognized it. So, to ensure the book didn't fall into students' hands:  Why didn't Snape keep or secure his copy of Advanced Potion-Making?   (Or did Snape want a student to find it for boastful personal reasons, just as Tom Riddle used the diary Horcrux to take credit for the Basilisk and being the Heir of Slytherin?)
87960
In the PHB under The Book's Appearance the text give two examples of how a spellbook looks like a book and one example with it being just a collection of notes.  Does a Wizard's spellbook need to be a book? Can a spellbook look or even be something else rather than just a book?  For example, could it be a series of small scroll tubes tied together like a rope ladder?  A necklace of marbles where each marble was inscribed with a single spell?  Elaborate wood carvings on a puzzle-box?  Colourful tattoos on the backs of slaves? (I'm not saying it won't be awkward when a Dragon eats pages 21 to 34 when adventuring, just asking if it would be allowed.)  Runes on the faces of convex regular icosahedron? ;)
106750
Why didn't Dumbledore show his memory of Barty Crouch Jr's confession to Cornelius Fudge to confirm his point that Voldemort returned? Wouldn't that just prevent all the mumbo-jumbo happening in the 5th book?
97813
Is there any mention on the abilities/capabilities that make Albus Dumbledore the finest wizard of his age? I know he defeated Grindewald and Voldemort was afraid of him too because of his magical knowledge.   What I want to know is as a reader, did we get to glimpse exactly what all those abilities were? We came to know that he was excellent in transfiguration (Book 5) and he could speak Mermish (Book 4) and Can perform magic using strange unknown languages (Book 2 and Book 6)..Also his work on Alchemy and Discovery of Uses of Dragon's Blood (Book 1).   Anything else that might suggest he was more knowledgeable than any other wizard alive?
88400
We know that you can't transfigure food, so you have to grow it or buy it. Ditto money.  I'm sure that aside from some medicinal plants Herbology Professor had there were no farmlands at Hogwarts. So they must have bought food (as well as potions ingredients for Snape etc...). And they needed to pay the teacher salaries.  Where did all that money come from according to canon?  Ministry funding?  Tuition?  Patent money on Dumbledore's inventions?  Philanthropic donations by Malfoys and co?  Other?
83969
This question was suggested to me by  which asked about the practicalities, but attracted many comments about the ethics.  So this question is to ask about the ethics directly.  Suppose I have written and published a textbook, and I want to use it as the text for a course I am teaching.  I receive royalties from each copy of my book that is sold, so if my students are required to buy my textbook for the course, I will make some money.  Is it ethical to do so?  Well-reasoned opinions would be useful answers, but even more useful would be pointers to institutional policies, professional codes of ethics, etc, that address this issue.  Of course, there are many ways to avoid profiting from the sale of my book to my students.  If my contract with my publisher allows it, I could distribute PDFs to my students, or have the university bookstore print out copies and sell them at cost.  Another approach I've heard of is to compute how much I earn in royalties on each copy, and refund that amount from my pocket to each student who buys a copy.  Or, use my royalty earnings to buy pizza for the class.  Certainly these are nice gestures, but I would like opinions on whether they are ethically required.  Edit: To address some questions that have arisen in the comments:   This question is hypothetical.  I haven't published any textbooks myself and have no immediate plans to do so.  In any case, my personal preference would be to make the book available to students for free, if at all possible.  So I've phrased this question in the first person for rhetorical convenience only. I had intended the question to be only about the potential financial conflict of interest that could arise if I make money by assigning my own book.  Some of the answers feel that it is improper for me to assign my own textbook at all, whether I make money or not, but I don't think this point of view is prevalent within the academic community.  If it happens that my book (as a pithy but now-deleted comment put it) "blows", I think most would agree that my decision to assign it is pedagogically unfortunate, but not unethical.   I don't literally mean that students would be required to buy the book, only that they'd be expected to have it.  I might assign readings or homework problems from the book, so that the student needs access to the book in order to do them, but they could certainly achieve this by getting a used copy or borrowing from a friend.  But probably most students would buy new copies anyway, since that is the most convenient way.
70477
Professor Severus Snape was a very important character throughout the Harry Potter series. He played very important roles in Harry's life as well as in Hogwarts fortune. His works were admirable and beyond expression in words.   But, with all due respect to him, I could not understand why he portrayed himself as angry, ferocious, tough and mischievous toward his students?   He always treated Harry and the students in a way which cause everyone to dislike him, except for his Slytherin students.  Why did he pretend to be so?   Was it because he could not get Lily and that Harry was the son of James, the hater of Snape?
18793
In Harry Potter and the Deathly Hallows, chapter one The Dark Lord Ascending, Voldemort believes he must use a wand other than his own in order to kill Harry, when Harry is moved from Privet Drive. He demands Lucius Malfoy's wand, and gets it.   My question is, why did Voldemort take the wand of one of his most loyal servants, rendering Lucius Malfoy useless if a battle was to occur?  If I remember correctly, he had Ollivander at his disposal, and he was the one who told him to use another wand in first place. Why not ask Ollivander to create another wand, or just use ones that he had ready to sell in his shop at Diagon Alley? He could even have taken Ollivander's own wand. If my memories are correct, a wand's importance was compared to that of a limb.
93039
Who was the rightful owner of the Sword of Gryffindor?     ‘So where is it?’ Harry asked suspiciously.   ‘Unfortunately,’ said Scrimgeour, ‘that sword was not Dumbledore’s to give away. The sword of Godric Gryffindor is an important historical artefact, and as such, belongs –’   ‘It belongs to Harry!’ said Hermione hotly. ‘It chose him, he was the one who found it, it came to him out of the Sorting Hat –’   ‘According to reliable historical sources, the sword may present itself to any worthy Gryffindor,’ said Scrimgeour. ‘That does not make it the exclusive property of Mr Potter.’   Deathly Hallows - page 109 - Bloomsbury - chapter seven - The Will of Albus Dumbledore   Scrimgeour doesn't go on to say the Sword of Gryffindor belongs to the Ministry, although he does say it does not belong to Harry. Even so, I'm sceptical enough of the Ministry's motives to conclude that a case could probably be made for Harry being the sword's rightful owner. But was he?  Is there a canon answer to this question? If not a direct answer from the books, a speculative answer in the spirit of canon is welcome.   Who was the rightful owner of the Sword of Gryffindor?
81161
Related to this question:  and   TL;DR - 1a) Do we know of any other students that were actually expelled?  TL;DR - 1b) What constitutes a complete education? Do all children have to pass OWLS and NEWTS?  The only example I can remember is: Hagrid. He was fully expelled, wand broken and everything.  It is also my recollection that the wand is broken because without a completed education the wizard will end up being a danger to the public by not performing spells properly.  However we see the following:   Fred and George left the school voluntarily so there was no official to confiscate and break their wands. They end up opening their joke shop.   Same goes with Harry and Ron so they can pursue the Horcruxes. They end up working as Aurors directly after the war. Hermione leaves but goes back and completes her education.    This leaves the following questions:   Since Fred and George did not finish, why did the Ministry not show up at the shop to confiscate and break their wands?  Same with Harry and Ron. Why when they went to work for the Ministry was nothing said or done?   Harry and Ron are the HEROS so I am guessing that no one would want to enforce the law in their cases. Kingsley actually recruited them to head up the new Auror department.   Fred and George, however, leave before the end of the war in a time where the Ministry is corrupt. So it would stand to reason that they would be targets.  We also know that many children are home-schooled throughout the world. So there must be some standard that the Ministry would deem acceptable to not go break the wands of all the wizards that are home-schooled.   It almost seems to that this is just a setup for Hagrid's character and role, plus a background threat to Harry whenever it convenient for the plot...     Edit to account for Fantastic Beasts and Where to Find Them:  We know that Newt Scamander was expelled from Hogwarts, but he definitely still has his wand!
119156
‘[...][Harry'll] be famous – a legend – I wouldn’t be surprised if today was known as Harry Potter Day in future – there will be books written about Harry – every child in our world will know his name!’   ‘Exactly,’ said Dumbledore, looking very seriously over the top of his half-moon glasses. ‘It would be enough to turn any boy’s head. Famous before he can walk and talk! Famous for something he won’t even remember! Can’t you see how much better off he’ll be, growing up away from all that until he’s ready to take it?’   Philosopher's Stone - pages 15 - 16 - chapter one, The Boy Who Lived   Did Dumbledore choose correctly?  Knowing what we do about Harry and his canon character attributes (And faults, too!), was Harry really better off enduring eleven years of physical and emotional abuse at the hands of the Dursleys than eleven years of celebrity and fame in the wizarding world? I'm sure we've all read about child celebrities who have done well handling fame, and some who have not fared so gracefully.   Would Harry have endured celebrity as stoically as he did the Dursleys' abuse? Did Dumbledore make the right choice in leaving Harry with the Dursleys instead of letting him grow up in the wizarding world?  Was Harry really better off?  ETA: I'm looking for an answer grounded in Harry Potter canon and written in the spirit of canon. Please do not pair Harry with Elle Fanning or opine that he's secretly an American ;) Thanks!
105001
Being born to James and Lily, how can Harry be called a half-blood?  It is said that admission in Hogwarts is given to children of Muggles when they show magical talents as a child, and Lily was no exception to this. This makes Lily a witch, so why is Harry half-blooded?
37828
The facts:   The job was cursed.       Oh, he definitely wanted the Defence Against the Dark Arts job. The Aftermath of our little meeting proved that. You see, we have not been able to keep a Defence Against the Dark Arts professor for more than a year since I refused the post to Lord Voldemort.   - Albus Dumbledore, Harry Potter and the Half-Blood Prince  It lasted From 1957 until the fall of Voldemort (1998)       1957 (Y-23) [Voldemort] resurfaces and applies to teach [Defence Against the Dark Arts] Ten years after the death of [Hepzibah Smith], [Voldemort] returns to [Hogwarts], where Dumbledore] refuses to grant him a teaching job. He then curses the [Defence Against the Dark Arts] position, and since that day, no professor has stayed for more than one year in that post. Again we don't know exactly when this happened, but since most evidence points to [Dumbledore] becoming headmaster in 1956 [[Y-24]], [Voldemort] couldn't have come looking for a job much sooner than this. (HBP20)  No one could hold that position for more than one year       It's well seen throughout the series that there is a "curse" on the DADA teacher position, that no one can hold that post for more than a year    Is there (preferably canon) information on:   How did Voldemort manage to do such a powerful curse? Why didn't Dumbledore, knowing about the curse, not do anything to lift it? Why didn't Voldemort put that curse in the headmaster's position, or on the whole Gryffindor house?
76448
In Harry Potter and the Half-Blood Prince, Dumbledore orders Harry to retrieve the memory about the talk with Tom Riddle/Voldemort from Slughorn. The memory is said to be needed because it contains valuable information that is needed to defeat him. The result is that they know that Voldemort uses Horcruxes.  Why do they not know this before? If the knowledge about Horcruxes is present in school books (albeit forbidden section) and teachers, then surely some magical academics will already have guessed that Voldemort would try to use them?  Also, if I recall correctly, there is a hint in the first book, "some thought that he was no longer alive enough to be able to really die" which hints a lot at the split soul as a price you pay for being immortal.  Why does Slughorn's memory seem so crucial to Dumbledore?
60735
Inheriting the magical blood down the line, via a wizard father or a witch mother is understandable in case of Half-Bloods.  I am wondering as to how Muggle-borns end up with magical ability?
26301
We know that Voldemort knew that Grindelwald was not killed by Dumbledore, as he himself killed Grindelwald.   We also know that Voldemort knew that Dumbledore was the last person to wield the Elder Wand with its full allegiance because he killed Snape in an attempt to inherit that allegiance from him, who he assumed inherited it from Dumbledore.   Now Voldemort is no idiot.   Following this chain of logic, based off of what he knew, he must have realized that Dumbledore didn't gain the wand's allegiance through murder as he never killed Grindelwald, so why did he feel the need to kill Snape in order to win the wands allegiance for himself?   Surely he must have known that disarming him would have been enough. Was he so blinded by his desire for the wand that he was willing to try anything? Or was he so pressed for time that he didn't fully consider the matter?   I can't imagine the latter to be true as Voldemort himself said to Snape before killing him that he considered the matter for a long time, but that, of course, could be a lie.   Or perhaps he decided that what with Snape no longer being a competent spy after being outed that he had outlived his purpose and would be more valuable dead as a result of this last ditch effort to gain the wands true power.  I'm just answering my own question at this point, but I'd like to put it to you all. Is there something I am missing here? Is there any word from JKR that can clear up this seeming lapse in Voldemorts judgement?
85261
I have tried to figure this out but I cannot come to a specific conclusion. I am just asking this to confirm my own theory.  In Half-Blood Prince, Dumbledore's memory proves that he was the headmaster when Tom Riddle came to ask for a professor's job at Hogwarts. He also tells in the same part that he was a professor at Hogwarts when he met the young Tom Riddle.  Also keeping his friendship with Grindelwald in mind, I would say that he was around 100 years old when he died.  Any more ideas?