Science Fiction & Fantasy Stack Exchange is a question and answer site for science fiction and fantasy enthusiasts. It's 100% free, no registration required.

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

The Sorcerer's (Philosopher's) stone was moved from Gringotts to Hogwarts because Dumbledore wanted the stone to be better protected. In Harry Potter and the Sorcerer's Stone however, Harry, Ron, and Hermione, three 11 year-olds, manage to get through seven magical obstacles designed to protect the Sorcerer's (Philosopher's) Stone.

If it was possible for three kids to get through the obstacles then how was the Stone well protected at at all. Did Dumbledore really expect that the teacher's defenses would work against Voldemort?

share|improve this question
Don't forget, Harry has the title character advantage on his side. – David Conrad Jul 14 '14 at 20:41
A bit like the way that people somehow always end up defending against James Bond using beautiful women, fast cars, parachuting sequences, drinking contests, fistfights, etc. That'll work, gets him right outside his comfort zone. A less perfectly capable protagonist, with less benefit of dramatic irony, wouldn't hit the sequence of X's on the stage floor that takes them smoothly through the mayhem and would be defeated. – Steve Jessop Jul 14 '14 at 23:49
What is this "Sorcerer's Stone" of which you speak? – Pharap Jul 15 '14 at 6:57
@Pharap In the EU it was called Philosopher's Stone, but AFAIK the producers thought this reference would fly over the heads of the american audience, thus they renamed the book/movie to Sorcerer's Stone. – zovits Jul 15 '14 at 9:51
@zovits which annoyed all of us who knew what the "Philosopher's Stone" was, but had no clue what the "Sorcerer's Stone" was. – rcollyer Jul 15 '14 at 14:55
up vote 76 down vote accepted

Let's step through all the obstacles.

  1. Idiot Test

    The door was locked and required Alohomora.

  2. Fluffy

    This giant, three-headed dog fiercely guarded the trapdoor leading into the actual chamber. I suppose that it would be possible to fight your way past it, but it was such a confined space and the dog was so big that it would be nearly impossible. Even for someone like Voldemort, I suspect that it would be difficult to kill Fluffy without waking up the whole castle or alerting the staff to his presence. The gang (Harry, Ron, Hermione) was able to get past Fluffy because they knew that music would put Fluffy to sleep.

  3. Devil's Snare

    Designed to kill anyone who landed in it, the Devil's Snare was a very clever means of thwarting thieves. One can't fight their way out of it, they have to use a spell. Knowing that Devil's Snare doesn't like heat probably isn't common knowledge in the wizarding community. But due to the fact the Hermione pays attention in herbology, the group can move on.

  4. Key Room

    Filled with flying keys, this room will stop anyone from advancing that can't find the key to the door. Good thing that the group had a quidditch prodigy with them to help them catch the key.

  5. Giant Chess Set

    The only way to move on here is to checkmate the enemy king. Because Ron managed to win against the chess set, it is safe to assume that the other side was not really playing to win, but rather seeking to divide any groups that had made it this far. Or Ron is really good at chess.

  6. Troll room

    In all honesty this isn't a very good obstacle. If you already got past Fluffy then the troll shouldn't be that big of a problem. This is probably by professor Quirrell's design because he wanted to eventually steal the stone for his master. Although if it wasn't already knocked out then Harry and Hermione would've had quite a problem on their hands.

  7. Potion Room

    Containing seven unlabeled potions, this room represents one of the hardest challenges to thieves:

    "Brilliant. This isn't magic — it's logic — a puzzle. A lot of the greatest wizards haven't got an ounce of logic, they'd be stuck in here for ever." -Hermione

    So Snape's puzzle tests something that none of the others do: that you can logically work through situations. This obstacle also divides groups up because there is only enough potion to take one person through the fire (It is unknown whether Quirrell drank half the potion or it refilled itself, in either case it was still a small vial). Because Hermione was there Harry was able to go on (not that he wouldn't be able to solve it on his own, but it certainly have taken a while).

  8. The Mirror of Erised

    One of Dumbledoe's more brilliant ideas, as he puts it, is to not allow anyone who wants to use the stone to have it. The only way to get the stone is to see yourself possessing it in the mirror. This is what makes the stone very, very well protected. Anyone that wanted to use the stone for their own purposes simply couldn't have it.


The stone is in fact very well protected. The group had a very specific set of skills that allowed them to advance as far as they did, and because Harry had no selfish intentions, was granted the stone.

share|improve this answer
Above all else Dumbledore's Test made it hands down completely safe. obviously due to a plot twist 2 separate groups managed to get to the final tests and 1 didn't want to use the stone (Harry) so the original thief could have just stolen it from Harry , again plot twist that Harry couldn't be touch yada yada ... Anyway no Thief would have Every gotten the stone. – Himarm Jul 14 '14 at 19:44
And let's not forget - Gringott's got broken into just after the stone got transferred, so at the very least Hogwarts security was that much safer. – Zibbobz Jul 14 '14 at 20:13
Obstacle 0: Hogwarts. To even get to the entrance, the person would need to be able to get into the corridor unnoticed. – Justin Jul 14 '14 at 21:20
To expand on Quincunx's answer.. Not only did they have to get to the corridor.. They have to get into Hogwarts itself, what was VERY well and subtly protected. V managed to find a sneaky way in, but getting into the school, once the staff was alerted, was a non-trivial problem. – K-H-W Jul 14 '14 at 22:17
Except for the last one, those all look awfully like 'security by obscurity' to me. Great for presenting the heroes of the story with a challenge that's interesting to watch and/or read about, not so much for actual security. – valderman Jul 15 '14 at 9:52

I think they were reasonably secure.

The Mirror of Erised alone is probably sufficient, but I think the others are also stronger than you give them credit for. Here’s my breakdown:

  1. Fluffy and the trapdoor.

    Larger creatures tend to be harder to attack. (Dragons and Blast-Ended Skrewts are a particular extreme.) Most people would probably lack the strength to stun or incapacitate Fluffy, so unless you killed him (also hard) or knew about the music, I think he’d be fairly hard to get past. He also serves as a useful deterrent to wayward students.

    Also worth noting that while Voldemort at full strength could probably kill Fluffy with ease, Dumbledore knows from Harry’s encounter in the Forest that Voldemort is severely weakened. He probably supposed as much when designing the defences. Many of these defences would crumble at the hands of Voldemort at the height of this power, but that’s not who Dumbledore is trying to defend against.

  2. Devil’s Snare.

    For this obstacle, you need to recognise the plant and know the counter-measure.

    Both Ron and Harry attended the same lessons as Hermione, but neither of them recognised the plant, nor knew the solution. When most people are faced with a dangerous situation, they panic (just like Ron does) – this is actually quite a clever defence, because panicking will just make things worse.

    Also, how much do you remember from when you were in school at 11? It’s probably not as much as you’d like to think.

  3. Flying keys.

    Even with a broom, it’s going to take a while to catch the key. Remember that in the books, the trio use a pincer movement to hone in on it:

    “We’ve got to close in on it!” Harry called, not taking his eyes off the key with the damaged wing. “Ron, you come at it from above – Hermione, stay below and stop it going down – and I’ll try and catch it. Right, NOW!”

    An individual acting alone would find it substantially harder to catch the key, and anybody who ventured down in a large group would probably be thinned by the next obstacle.

  4. Wizarding chess.

    I think this serves two purposes: to slow you down, and to divide a group of attackers. It does both quite well.

    Chess is generally not a fast game: rushing causes mistakes. If human lives are at stake, this is a poor approach. More on time in a minute (pun intended).

    If every person in your party has to replace a piece, then it’s more likely that one or more of them will be injured or killed in the course of the game. This reduces the advantage of numbers as you advance into later chambers, and may have an emotional impact on the group (witness Hermione’s distress at Ron’s injury).

  5. Mountain troll.

    Like Fluffy, this is unlikely to yield to brute strength. Unless you know about trolls in particular (or have an invisibility cloak, perhaps), I don’t see the average person getting past this easily.

  6. Logic puzzle and potions.

    As Hermione explains, this plays to a particular weakness of many powerful magicians:

    “Brilliant,” said Hermione. “This isn’t magic – it’s logic – a puzzle. A lot of the greatest wizards haven’t got an ounce of logic, they’d be stuck in here for ever.”

    Even those with some modicum of intelligence (like Hermione) will be slowed down while trying to work out the clues, and you’ll be careful because your life is at stake.

  7. The Mirror of Erised.

    This is easily the strongest obstacle (although we don’t know what was guarding the Stone before the Mirror). Despite his prodigious skill, Voldemort seems completely baffled. Had Harry not turned up, he could have taken a very long time before he got to the Stone.

    Dumbledore sounds particular proud of this invention:

    “It was one of my more brilliant ideas, and between you and me, that’s saying something. You see, only one who wanted to find the Stone – find it, but not use it – would be able to get it, otherwise they’d just see them- selves making gold or drinking Elixir of Life.”

    I think the Mirror would make him confident in the Stone’s safety.

I’d make a few other observations:

  • Even if they don’t keep an intruder out, they still slow them down.

    The keys, chess and logic puzzle would all take significant time to get past. All of this gives Dumbledore time to be notified of the intrusion, and move to engage or hinder the would-be thief.

    Even when he’s diverted to London, Dumbledore is still able to arrive in the final chamber shortly after Harry. Had Harry not tried to reach the Stone, Voldemort would still be attempting to break the Mirror. And if Dumbledore was in Hogwarts when the intrusion started, then an intruder would have no chance of getting through every chambers before Dumbledore arrived.

  • They require diversity of skill and knowledge.

    Yes, these chambers are defeated by three eleven-year-olds, but each one of them is necessary. Each chamber required a particular set of skills – skills rarely, if ever, found in the same person. Quirrell, who fought through it alone, had significant foreknowledge of the protections. I think a single person who went in with no knowledge of the defences would really struggle.

share|improve this answer
Your observations at the end really made me think: the biggest flaw in the design of the defenses was that it gave no notification on any break-in attempt. They are really useful in slowing down intruders, I guess Querrelmort needed quite some time to arrive to the last room. By that time, Dumbledore should already be waiting for him, maybe with a group of Aurors. It's strange to believe that there was no monitoring of any of the rooms. Or was it? Dumbledore finds Harry quite quickly after the events, so he might have been monitoring him the whole time. In this case, why didn't he intervene? – vsz Jul 15 '14 at 6:16
@vsz If Dumbledore had a back way in, in order to be waiting for the intruder, then the intruder could have just gotten in that way while Dumbledore was out somewhere and avoided all the traps. Not a good plan. – Izkata Jul 15 '14 at 23:16
@Izkata : unless, for example, no one can apparate inside the building except the headmaster. – vsz Jul 16 '14 at 3:02
So Dumbledore's comment from Prince chapter 26 applies: ‘The protection was … after all … well designed, […] One alone could not have done it … you did well, very well, Harry …’ – b_jonas Jul 17 '14 at 5:40
I 1+ because of logic and canon, but the security was lacking if a bunch of misfit 11 yr olds can break in, ie. you have no security. I don't care if it took if it 100 of them, if some kids in their first year can break through then upgrade complexity. The security was not advanced, they used simple spells and logic. So my answer is that the security sucked. – Pobrecita Jul 17 '14 at 9:43

The challenges are fairly solid if you approach them in the way they're designed, but I don't think they're resistant to cheating.

Fluffy: This one's pretty good overall. Hard to bypass unless you know the secret, makes a good early warning for nosy students.

Devil's Snare: If the attacker can levitate and shoot fire (and what self-respecting wizard can't?), this one's not much of a hazard. However, it provides a soft landing for nosy students who jump down a trap door blindly.

Flying keys: Seems pretty difficult, unless they're a nosy student who happens to be an ace Seeker. However, a more powerful wizard could easily cheat this: "Accio Silver Key."

Wizard's Chess: Seems like a good obstacle. As powerful as wizards are, getting bludgeoned by a giant stone statue will hurt. Takes an unusual skill to bypass that an attacker may not have. Giant stone statues seem resistant to brute force.

Troll: Seems a little redundant after Fluffy, but unlike Fluffy, there's no easy way for a nosy student to bypass this. Quirrel just knocked it out with brute force.

Logic Puzzle: Three words: Flame-Freezing Charm. But if Hermione is right about wizards not having much logic, I suppose this is a good trap.

Mirror of Erised: This is the big one. A thief, by their very nature, can't bypass this. There doesn't seem to be an obvious brute-force solution, either. You need a nosy student (stopped by the troll earlier), or I guess Dumbledore himself.

So basically, we've got five obstacles that can be bypassed by nosy students or brute-forced by a stronger wizard, one obstacle which can't be passed by nosy students, and one that's totally bulletproof. So my theory is the first traps are designed to be a good adventure for a group of nosy students, while the troll keeps nosy students out of the real security system. The final challenge can actually stop thieves.

share|improve this answer
We actually have obstacles they are made to slow down but they always give you a way in. – Sulthan Jan 19 '15 at 23:13

Most of the security was not based on the protection from the teachers. It was based on Hogwarts Castle being secure.

Hogwarts security is mentioned multiple times in the book - you can't apparate there, you can't even reach it on a broom (in the end of book 6, Dumbledore has to remove protecting spells to reach the tower). The Death Eaters couldn't get there without the vanishing cabinet.

The protection from the teachers was just an additional level of security and it was there because of the plot.

The security was silly to begin with:

  1. Fluffy - an animal, probably possible to be killed by magic. If not, it has to sleep sometimes. Using an invisibility cloak or some other magic could probably enable any wizard to pass it unnoticed. If not, evil wizard have lots of options, for example, taking someone else there and using them to lure the beast to the other side of the room. Also, someone has to feed Fluffy. Listening at the door how that one is dealing with Fluffy when bringing the food is the most simple way to learn about that music stuff. Another option would be to study books about handling this kind of animals.

  2. Devil Snare - something that everybody learns in school in their first year, so probably something pretty basic. The chance a potential attacker will know it is great. If not, fire is probably the first thing they would try. Or, they would be cautious enough not to jump blindly into nothingness - they could fly down creating light with their wand, for example. This would work much better by removing the Devil Snare - killing buglars instantly by the long fall and hitting the floor.

  3. Flying Keys - some powerful magic could probably attract the key or just break the door. Note that Dumbledore was able to get past this pretty quickly, so he had to have another key or he just used a more powerful magic. Why having the keys there at all? Why not just wear the key in your pocket instead? This is just making it easy for the buglers.

  4. Chess - why Chess? Why not an army of Chess pieces attacking anybody entering the room? Why the chess pieces were not a bit more clever? If a 14 years old boy could defeat them, what's the point? Again, Dumbledore was able to get past this room quickly, so he either smashed the pieces by magic (in the beginning of book 6 Voldemort can apparently destroy whole bridges), or he had some kind of backdoor. Allowing a burglar to pass through this room just by winning a chess game is a huge security breach.

  5. Troll - worse than Fluffy. Can be knocked out easily so also killable by magic easily. A very difficult security measure because it has to be fed. That means that someone has to go there every day and feed it (note that food cannot be created by magic). The interesting idea is whether they made the troll to learn Dumbledore's smell or whether they just knocked out the troll everytime they went to check on the stone.

  6. A very simple logic puzzle. Again, the question is why giving hints at all. Why not just keep the correct vial in you pocket and remove everything else from this room, keeping only the fires.

  7. Mirror of Erised - a psychological protection. Harry found the stone because he wanted to find it. Quirrell didn't find it because he wanted to give it to Voldemort. Frankly, this is more based on a play with words than on psychology. I don't think this is a good protection and there are too many questions involved. For example: would breaking the mirror destroy the stone? Where was the stone actually stored?

On a side note, a more direct approach would be to find Nicolas Flamel and beat the hell out of him to get a vial of the Elixir.

share|improve this answer
This always bugged me too.... it seems like the protection was not for the stone per se, but rather to provide decent plot line for us to enjoy – Abhinav Nov 26 '15 at 6:32

The points the others are making are quite valid. The stone was very well protected once it was in the mirror. But no, there was a lot of risk to the stone before that point. Hagrid had the thing wrapped in paper and put in his pocket. He is not exactly the least absent minded person in the wizarding world but even if he was much more aware of his surroundings transport of an object such as this one should not have been left to just Hagrid.

These 11 year olds also managed to break into Gringotts in later movies through skill more than a lucky mixture of skill sets. This shows that the stone did have to be moved. The method of that transport was not the most secure and well thought out. A port-key waiting at the entrance of Gringotts might have been a better plan. Speed, low profile, no undo risk.

So, in conclusion, there is a lot of evidence suggesting that the security of the stone was not supposed to be unbreakable. I think Dumbledore had an ulterior motive. Perhaps to draw out the bad characters.

share|improve this answer

As has been pointed out, Dumbledore's technique to require someone who doesn't want the stone, is very good, and the other tests have a good mix of strengths. Also Dumbledore seems to have had the wisdom to have an opening for what in fact happened, to happen - a very gifted group of students could survive it, and this could be a very good thing. In this case, elaborate obstacles actually served a purpose, since it was in a wizard academy and he was aware of the great importance of especially gifted pupils to the whole scheme of things.

What strikes me as particularly lacking, however, is effective alarms and backup security, though maybe this was due to an even greater level of Dumbledore's wisdom, possibly extending to the level of knowing this was best. However from a practical point of view, assuming you think that one could deal with the worst of thieves if one could catch them, then I would think one would want an alarm component of each stage, so that one could know and respond actively to the intrusion.

share|improve this answer

I think that the main obstacle would be the chess game. Currently, the best computers can beat grand masters. So logically, the pieces could be enchanted with similar rules (and white would always win). Assuming that wizard chess is essentially the same as muggle chess, either Ron and Prof. Quirrel are way beyond grand master level (unlikely) or Prof. Mcgonagall isn't quite as good at enchanting as she could be.

share|improve this answer

If you remember a backup alarm would not done any good during the end of a school day. After all most of school was on break after Finals.

Dumbledore was called way by they Minister of Magic.

As for Ron beating Wizards Chess. Its possible that he could been playing the game with his brothers for years before going to school.

Finally Hermione is a very intelligent book worm. She can memorize anything.

Potter is the chosen one and named after the book.

share|improve this answer

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.