Isn't any science that is [sufficiently] beyond the understanding of the viewer, looked upon as magic? I think we have a different definition of the term "magic".
Would someone in the 1600's not think penicillin and vulcanized latex were magic? What about holography? Alchemy is not another word for chemistry.
In a fantasy setting though even regular plain old chemistry should be considered magic. :shrug:
I don't consider it a game without them. :shrug:
Spoiler Its true that Fallout (1) didn't have them, so call it my double standard... But Fallout wasn't a fantasy game. :shrug:
Actually, Fallout
was a fantasy game, with Magical Glowing Zombies, wierd brain-things, and Giant Mutant Ogres.
As far as why Alchemy's a stealth skill now, We can use the process of elimination to show it's not magic:
Does it involve drawing on the user's pool of magicka for its effects?
If yes, it's magic, if no, then:
Does it rely on the user's knowledge of magical effects he can draw upon at will?
If yes, it's magic, if not... It ISN'T!
Alchemy has no "Caster", and it doesn't draw upon the user's mind directly. It's entirely self-contained to the predetermined effects of the ingredients being combined, to create the desired result.
The difference in mage, Fighter, and Thief is about the
mindset to problem solving (As evidenced in the character-creation questions from the first two games), not the actual activities. Alchemy uses a clearly defined set of parameters, and a Thief exploits those parameters to get the effect he wants from what he's given to work with, though the method and effect of his actions to solve the problem are not immediately apparent. (How is that scrawny thief supposed to haul that valuable suit of Ebony armor?! It's too heavy for him to lift! ...what's he doing with that piece of venison, sweetcake, and bottle of water? Ohh...)
The fighter takes a given problem at face value, and solves the problem in the most direct way. When confronted with a locked door, he'd use a key, or bash it down.
The thief, when confronted with a problem, works within the supplied environment to solve a given problem. He'd use a fighter technique when it works, but lacks the power to use it to solve all problems. He's also mindful of longer-term consequences of his actions, planning in advance.
Mages are just spoiled brats who've memorized the rude gestures and ancient expletives to throw a temper tantrum until the universe gets sick of their [censored]ing and buys them a gumball/decides a door isn't really locked/ignores the effects of fire on him/puts a band-aid on his boo-boo or whatever, limited only by the mage's ability to tantrum until the universe gets sick of them and says
no. This is also why all mages are smug twits with superiority complexes.