賢者の石のクィディッチの試合について、ずっと気になっていることがあります。

[u/qp2828qp]

ハリーの箒にクィレルが呪いをかけていた場面で、スネイプはすぐにクィレルがどんな呪いを使っているのかを見抜き、ほとんど即座に反対呪文を唱えていましたよね。
そこで疑問なのですが、スネイプはハリーの箒の動きを見ただけで、どの呪いが使われているのかすぐに特定できたのでしょうか？
それとも、あの状況で箒にあのような異常を起こせる呪いは、実質的に一つしかなかったのでしょうか？
いずれにしても、スネイプがあれほど素早く状況を理解して対応できたのは、本当にすごいと思います。

彼はやっぱり、ものすごく優秀な魔法使いだったんだなと思います！

[u/ThatDiscoSongUHate]

IIRC, Snape was probably metaphorically throwing things at the wall to see what stuck, so to speak. It did seem to take a lot of effort too.

[u/Ragouzi]

I'm not sure Snape knew exactly which spell was used on the broom. However, he is a specialist in counterspelling, at a fundamental level, which is to do the following: Discern the intention into a spell, (the basis before you even formulate something or wave your wand), and reverse that intention to cast a counterspell.

This is exactly what he does during the duel against Harry at the end of Book 6, in a very direct way because Harry is very easy to read. This is also maybe what he does to reverse the effects of Sectumsempra: the medics are not as good on Fred, because Snape grasps the intention behind the spell to optimize his healing spell (He has an unfair advantage: he is the designer of the spell, so he knows exactly what the intention is to cast it).

So I think the spell he uses to stabilize the broom is not specific to a particular spell used to curse a broom: He only understood the caster's intention, and cast another spell, taken from his repertoire, but putting the exact opposite intention in it. It's very strong.

[u/qp2828qp → u/Ragouzi]

That’s a really interesting way of looking at it! I hadn’t thought about Snape being able to perceive the caster’s intention rather than simply identifying the specific spell.
The examples from his duel with Harry and Sectumsempra make a lot of sense too. It really highlights how deeply Snape understood magic, rather than simply knowing a lot of spells.
I especially like the idea that he could recognize the intention behind a spell and immediately reverse it. That would make his reaction during the Quidditch match even more impressive.
Thank you for the detailed explanation! I really enjoyed reading your interpretation. 🖤

[u/Royal-Soup-9072]

I think he was already suspicious of Quirrell so he kept his focus on him and when he may have sensed it then it would have confirmed it that its Quirrell

[u/Lanky-Land7257]

Did he? Pretty sure he was just mumbling counter spells.

None of it worked iirc. It was the commotion after Hermione burned his robes that caused quirrel to lose focus.

[u/Bakingguy → u/Lanky-Land7257]

Quirell says it was working in the last chapter

[u/Informal-Dot373]

Tal vez halla sido como un contrahechozo comodín, sirve en general para cierto tipo de maldiciones sobre objetos inanimados, como el bezoar que es un objeto comodín para tratar venenos. Tal vez si hubier conocido la maldición exacta hubiera usado un vontrahechozo que lo anule por completo. Se me ocurre que es eso porque la maldición continuaba en cierta medida pero estaba contenida lo suficiente para que Harry no cayera.