Finn: Solo, we'll figure it out. We'll use the Force!
Han Solo: That's not how the Force works!
Han Solo: That's not how the Force works!
"Now you might think I'd be all over this shapeshifting business, Paxto, but if comic books, cartoons, and Sci-Fi Original Movies have taught me anything, it's that shapeshifting comes with a bunch of boring rules and restrictions that limit its potential Turn-Into-A-Bulldozer-Whenever-I-Wantity. 'You can turn into a machine gun but not bullets.' 'Contemporary jazz turns you back to normal.' 'You can only turn into presents your grandma's knitted for you.'"
"But Magic is as Magic does. Just funny that way."
An author's ability to solve conflict satisfactorily with magic is directly proportional to how well the reader understands said magic.
Fun fact about voodoo, Larry: can't conjure a *thing* for myself.
Y'see, demons can't resurrect people unless a deal's made. I know, red tape, it'll make you nuts.
— Azazel, Supernatural
But even though humanity had figured out how to break some rules of the universe under certain circumstances, like using the jump drives to travel faster than light between stars, the ways to break the rules had their own rules.
"Genies are only fun in the movies if you define and limit their powers."
The Plot: A team of scientists shrink themselves to go inside a patient's body in a tiny little spaceship, in order to fix a blood clot in his brain. They have only an hour, and then they will return to normal size.
The Hole: We don't ask that you stay within the bounds of physics, but at least follow the rules you freaking made up. At the end of the movie, the crew's tiny sub gets destroyed, but the team manages to get out of the guy's body just before they grow back to size. Only problem, they leave the wreckage of their miniaturized submarine behind. As clangers go, that's about as bad as you get. Anyone paying attention to the plot of the movie is wondering right up until the end when the giant submarine wreckage will be bursting out of the guys chest.
"Its very TNG to take something that the Original Series did so naturally (place the weirdest things like Nazis and hippies in the future) and give it a technological reason for happening like the holodeck or because of the power of the Q. This show is far too stuffy to just let these insane things take place simply because. Internal continuity is shot to hell this season as when you leave the holodeck you can bring things like water and lipstick with you…these things are not confined to the hologrid, which surely suggests that anything can walk off the holodeck onto the ship?"
...but one thing [Speed Racer] did right is that it didn’t bother explaining why Speed Racer lived in this crazy-ass world with these crazy-ass cars driving on crazy-ass racetracks, and also why they had a monkey. The point is that if you start your movie with the premise “this is how things are,” audiences will, more often than not, be fine with that so long as you suspend their disbelief and never question your own narrative.
— Mightygodking on superhero movies
The natural assumption is that any subject that can be taught to students in such a way that their competence in this subject can be tested by examination is a science.
— Gareth B. Matthews on magic in Harry Potter, Harry Potter and Philosophy
For all its faults — and make no mistake, there are many — Batman & Robin has a consistent internal logic. It constructs a world in which it’s okay for all this stuff to exist. Which is exactly what Nolan does in his films, albeit with a completely different idea of what “making it okay for this stuff to exist” actually means.
— Chris Sims on Batman & Robin
But when the wizard is onstage as the main character, you have to adopt what I call the Jack Vance Rule. (I call it this because Jack Vance is the first author successfully and adroitly to have applied this rule in his The Dying Earth). The rule is (1) The wizard has to be able to do something unusual, or else he is not a wizard (2) he cannot do everything, or else there is no drama; therefore (3) the story teller has to communicate the reader whatever the dividing line is that separates what the wizard can do from what he cannot do, so that the reader can have a reasonable expectation of knowing what the wizard can and cannot do.
For science fiction [and by extent, fantasy], you establish a framework - you establish the rules. Now you've gotta be honest in those rules. You can't just do anything you want to do because it's science fiction, otherwise it doesn't become particularly believable.
Think of the mystic arts as paintings. Limited by what she is, a vampire, werewolf or other such creature uses a paint-by-numbers set - a very powerful paint-by-numbers set but a set just the same. She's bound to a certain pattern, certain colors and certain results. No matter how powerful the vampire, Auspex will not make a person's head explode from across the room. Auspex always follows a set pattern.
A sorcerer uses a similar paint by-numbers set. The colors are a little brighter, the brushes slightly more flexible, but the end result is more or less the same. She may get very good at what she does, but the design was created long ago and nothing the magician can do, short of throwing the whole set away, will change the painting much.
Awakened mages pitch the paint set out the window and begin with clean canvases. They use similar mixtures and brushes - the Spheres - and begin their careers with similar templates - rotes, magick styles and foci. In time, however, a True Mage realizes that the designs and tools are unimportant. She begins to finger-paint with reality, to splatter the canvas and let the paint drip and do all kinds of Jackson Pollack stuff. Like Pollack, she makes a mess - Paradox - but in the end, her paintings are her own. If she's really talented, she might eventually learn that the paint itself - the canvas itself - is unimportant. She transcends the painting and becomes art. In short, she Ascends.
—Mage: The Ascension - Sorcerer: The Hedge Wizard's Handbook