It has been said that “Any sufficiently advanced technology is indistinguishable from magic” (Arthur C. Clarke—and while I’m quoting him, check out this site listing some of his other quotes, some are pretty good). I would tend to agree. I’m quite convinced that a modern computer would be regarded as a magical device by a secluded tribesman, or—going even more primitive—a monkey. They would be baffled by how such a device works, explaining it, no doubt, with recourse to mythology and mythic powers (assuming monkeys can even entertain such thoughts). I was about to propose a corollary to the above quote, then I did a search on the net and found this site: it is quite interesting; it seems the corollary evokes quite heated responses from the scientific community. I’m going to give my corollary anyway: “Any well-developed system of magic is intended as a form of alternative technology or science.” I’m not saying the magic actually works here on our lovely planet Earth, but rather, the magic as described in a fantasy setting is postulated as working in a situation where alternate rules apply. It could be an alternate planet, or more probably, an alternate universe.
There may not be practical utility in noting this, but I find it interesting. It kind of occurred to me as I worked on developing my world for my fantasy books (the first of which is “Drasmyr,” a dark fantasy featuring a vampire bent on destroying a wizards guild, now available for free at Smashwords). I’m also, on the side, developing a pen and paper RPG game to go with it. Anyway, the system of magic is complex and detailed. Let’s take potions. In my world, wizards can make potions. Generally, the process involves obtaining various ingredients and combining them so that their properties interact and evoke a desired result. The basic assumption behind this is that each of the ingredients has certain properties which can be harnessed with diligent effort. Is it not unreasonable to assume they are using an alternative Periodic Table or something similar that operates according to their own rules, so that alchemy in a fantasy world is something like a “parallel” form of Chemistry or Pharmacology? Magic in the fantasy world generally is not something quick and simple; it takes years of study and discipline for a human being to become a wizard and learn magic. Of course, using magic to blast something with a ball of fire might be stretching things a bit… but if we can have electric eels in this world, a fire-wielding spell-caster in an alternate reality might yet be feasible. And the rules that govern the fire-wielding spell-caster will no doubt require years of diligent effort to master. At this point, I don’t see much of a difference between science and magic: it is simply different rules give different results. Well, at least, in theory. In terms of practicality, it would be impossible and really foolish to try to spell out all the rules of a magic system at the same level of detail that we have for modern science. That would be the work of lifetimes, for something that doesn’t exist.
Additionally, if you play with the rules too much, and you follow them strictly out, the resulting universe could very well be unintelligible to us. No one wants to read very much about a “gak that blops a trebid.”