Basic Trope: A character can do the impossible because they don't understand that it's impossible.
Straight: Therm can ignore gravity because nobody ever told him how it works.
Therm can rewrite the laws of physics by not understanding them.
Therm can do the impossible when he doesn't understand that it's impossible, because he doesn't know that Achievements In Ignorance are themselves impossible.
Downplayed: Therm can do high-level calculus easily because nobody ever told him it was hard.
Therm is a Reality Warper but doesn't quite know it yet, and is unconsciously affecting the world around him based on his beliefs.
Therm is in a dream, and as such can change the rules whenever he wants.
Therm could Limit Break without hurting himself because the limit was actually mentally imposed, Therm never knew that there was a supposed limit and could activate it whenever he wanted to.
A character can't do something because he didn't realize it's possible.
Brian knows not only that it's impossible, but why... And from there, figures out how to make it possible.
David is aware of, and frequently exploits in-universe glitches.
Subverted: He really knew it was impossible. He's just that awesome.
Double Subverted: After he says that, someone points out that its impossible to do something on virtue of awesomeness alone.
Therm can't do anything that he can understand, but can do anything he can't understand.
Not knowing that such a thing is (literally) inconceivable, Larry conceives of, and draws, a four-sided triangle.note It's never shown to the audience or readers.
Zig Zagged: Therm can create impossible things and do impossible deeds because he doesn't understand that they're impossible- but then it is revealed that he does understand and is feigning ignorance- until they find that he isn't just feigning ignorance, but is in fact powering his achievements with Clap Your Hands If You Believe and is consciously ignorant, carefully keeping himself from new knowledge- but this revelation damages his ability to create, as he knows how he is capable of these feats and thus can no longer be capable of them- then someone hits him with a hammer and it's all back to normal.
Therm knows exactly what he's doing, and how he's doing it.
Therm tries to do something. Not knowing it's impossible, he keeps trying and trying and trying and trying. He's getting nowhere.
Enforced: "You know what'd be funny? Someone not falling down a cliff, because they didn't know they were supposed to!"
Lampshaded: "Big Bad's plan may be foolproof, but it's not Therm-proof!"
Invoked: "Yes, what Therm's doing is impossible, but don't tell him that!"
Exploited: Therm is sent off to perform some task because of his ignorance of its impossibility, and the others make damn sure he doesn't find out it's impossible.
Defied: While Therm is standing midair, someone hands him a physics book.
"Someone should tell Therm you can't ride a T rex while flying a rocket at the same time."
"If one doesn't understand the subject matter of what one is attempting to invent or achieve, one is simply trying random things one after the other, hoping to hit a bulls-eye. One won't even achieve the ordinarily possible, let alone the impossible."
Conversed: "It's amazing what can happen in fiction if the characters don't pay attention in physics class."
Therm is taunted for his ignorance and decides to become intelligent by studying hard. Because of this, Therm loses what really made him special since he now understands limits of reality, and can't accidentally cross them.
Gravity only affects those who already know about it, so there's no way to learn about it in the first place. As a result, there is no gravity.
Therm is the most powerful warrior, not because he can handle his weapon, but because he can unlock his true potential whenever he wants to, and gets forced to move away from those he cares about because of this ability. They later find out that his ignorance actually had a reason for overcoming the limit, and bring him back so they can find out how to.
Therm convinces himself that there's a magical force that pulls distant objects towards each other. As a result, he manages to fall, since he didn't know it was impossible.
Back to Achievements In Ignorance.note Wow!.. How did you do that? That wasn't a real link!