“One of the things a lot of people don’t understand about magic is that the rules of how it works aren’t hard-and-fast; they’re fluid, changing with time, with the seasons, with location, and with the intent of a practitioner. Magic isn’t alive in the sense of a corporeal, sentient being, but it does have a kind of anima all its own. It grows, swells, wanes, and changes.
Some facets of magic are relatively steady, like a person with a strong magical talent fouls up technology—-but even that relative constant is one that has been slowly changing over the centuries. Three hundred years ago, magical talents screwed up other things—-like causing candle flames to burn in strange colors and milk to instantly sour (which had to be hell on any wizard who wanted to bake anything). A couple of hundred years before that, exposure to magic often had odd effects on a person’s skin, creating the famous blemishes that had become known as the devil’s mark.
Centuries from now, who knows? Maybe magic will have the side effect of making you really good-looking and popular with the opposite sex—-but I’m not holding my breath.
I mean, you know.
I wouldn’t be. If I still had any.”
Harry Dresden musing, as a ghost
Ghost Story by Jim Butcher, chapter 14