Gamp's Law of Elemental Transfiguration
To be honest, I don't think that J.K. Rowling actually created five exceptions of transfiguration. I actually just think that she needed some laws to tell us what wizards can't - it wouldn't be funny or interesting to read about Harry, Ron and Hermione running around and just create everything they need out of thin air. So she created one rule, said there are more than one, so fans don't see flaws in her storytelling. But she mentioned that it's impossible to create money with a spell. So we know only two exceptions.
Here my thought list (bold is the known Laws of Gamp):
Food: We know that it's impossible to create food out of thin air. While it's possible to transform food or duplicate it, and of cause make animals and plants grow much faster, it's impossible to use the wand and create food out of nowhere. This is the only exception of transfiguration we know.
Hermione: "Your mother can’t produce food out of thin air, no one can.
Food is the first of the five Principal Exceptions to Gamp’s Law of
Ron: "Oh, speak English, can’t you?"
"It’s impossible to make good food out of nothing! You can Summon it
if you know where it is, you can transform it, you can increase the
quantity if you’ve already got some..."
Hermione Granger and Ron
Weasley on the exceptions to Gamp's Law
Love: We know that it's impossible to create love. Love potions etc. don't create real love, but it can create a sense of infatuation and obsession. Slughorn mentioned that it's impossible to create real love. Meanwhile, Dumbledore actually said that the Ministry of Magic has true love locked up.
"There is a room in the Department of Mysteries that is kept locked at
all times. It contains a force that is at once more wonderful and more
terrible than death, than human intelligence, than the forces of
nature. It is also, perhaps, the most mysterious of the many subjects
for study that reside there. It is the power held within that room
that you possess in such quantities and which Voldemort has not at
all."—Albus Dumbledore to Harry Potter on the power of love
Money: J.K. Rowling told us in an interview, that it's impossible to create money out of nowhere, or the magical world wouldn't work. I think the same goes for gold etc. Why? Because it would ruin the economy.
"Count yer coins! A' there's no point in tryin' to steal any, Goyle,"
he added, his beetle-black eyes narrowed. "It's leprechaun gold.
Vanishes after a few hours." (GoF pg. 544/472)
But it's possible to create gold and money with alchemy.
Soul: It's possible to create NEW life, but it's not possible to get someone back from death.
Information: While it's possible to increase your intelligence, gather information, make yourself more clever, take information from your head and put it into another one and, in general, is possible to manipulate with what you know; it's not possible to wave your wand and get the solution.
Yes, there are correcting feathers and feathers writing the correct answers; but I think it's very limited in some way. Else Dumbledore (or everyone else) could easily get the information about Tom Riddle in fractions of a second: or just create new spells in no time.
So yes, it's possible to gather information and make yourself clever and more knowing, but it's not possible to create information out of nowhere.
But then, it doesn't cover everything. Since potions aren't food, it should be possible to create it out of thin air (if our five exceptions are true).
Here a list of things it doesn't cover:
- Healing every wound in seconds
- Create new humans with a spell
I think it's smart of J.K. Rowling not to give us the solution. Since we don't know all exceptions, she can say that many of the flaws in her story are covered by this law. Simple.
Not to mention that there are a lot of flaws in her storytelling: like, why are there poor wizards? Why can't e.g. Lupus just use magic to create new clothes?
I love the Harry Potter books, but she needed to come with some borders; it wouldn't be a funny story if all wizards are rich, socially equal and Harry Potter, Ron, and Hermione hunt Horcruxes from a luxury hotel with spare bath. We just need some people to be poor to feel with them.