system
Given the following post, respond as if you're commenting on Reddit:
human
[Harry Potter] what makes a wizard powerful?... scientifically speaking, of course.

okay. So the magic in the *Harry Potter* series is probably pretty unintelligibly subjective, right? To the extent that (I'd imagine at least) it's difficult to talk about clearly, since magic includes weird abilities, like:

\-the ability to change your shape

\-the ability to read the minds of others

\-the ability to force your will upon others, using telepathy

\-other things which, if taken in all of their implications as the series gives us, probably lead us to some contradictions (i.e. is it possible for *any* spellcaster to be a powerful opponent against one in a duel, if one can read the other's mind and the one whose mind is being read, must speak their spells out loud.)

So I understand that in a duel, it will be a most useful trait to be able to do things like send spells without saying them, read your opponent's thoughts, and cast powerful spells. But what else is being measured between two fighters in a duel? 

Take, for instance, the duel between Voldemort and Dumbledore, at the end of *Order of the Phoenix*. Theoretically during this fight, each of the duelists has one person they could have assist them (Harry for Dumbledore, and Bellatrix Lestrange for Voldemort) which, iirc, doesn't actually happen. But is either wizard (Voldy and Dumble) so powerful that the other two are just useless during this encounter?

If Dumbledore sends out a spell and says to Harry, "Now for the rebound!" and Harry casts a complementary spell, they're only going to help each other out so that they win, right?

That's what I'm finding confusing, I guess. I mean throughout the series "powerful magic" is shown, and hinted at as existing far beyond the experiences of one human or another; however, what is the actual nature of some of the more powerful spells shown? Are Dumbledore and Voldemort just throwing big elementals at each other during this duel (in particular, because I feel that it showcases some pretty powerful magic between two dueling wizards where otherwise duels tend to forward more dramatic issues of the plot); or are they using magic that is just so far advanced beyond an average wizard's understanding of magic  (or, potentially, Harry's or Bellatrix's), that a novice wizard is going to be completely impossibly outmatched (or not be able to be helpful)? Or is there more nuance to it than that, like a novice could've stood up and helped but Dumbledore was exclusively trying to protect Harry (because Harry was important to Dumbledore's political endgoals); and Bellatrix either isn't that powerful (and she knows it), *or* she was afraid of Dumbledore because Dumbledore is a very wise, and very old, and very powerful, character?

Thanks. This has been confusing me and it's difficult to articulate the nature of this kind of question imo.
gpt
If i'm understanding your question corrextly, Imagine it as working in the same way as raw strength and training. Different people have different innate magic "strength", and different levels of training.  


Imagine Hermione as someone who's really buff, and is training to be better. Someone like Ron is pretty strong, but isn't putting in the effort to use that. Someone like Neville is naturally weak, but is training really hard to be decent at fighting anyway. And Dumbledore and Voldemort are people who are both naturally ripped and heavily trained  


They're the magic equivalent of, say, Muhammad Ali- not *technically* unbeatable, but might as well be for a normal person, or even for a normal boxer. They both know a lot of magic and are able to put a lot of power behind that magic meaning, yes, most other wizards are completely outmatched. They're simply top of the game, and only need to worry about the few others who've reached their level.