I've got a theory.
It's more of a mental thing.
You know, along the lines of super powers like the X-Men and whatnot.
It's a part of the brain that's dormant in most people, or some mutation, which allows the person to "cast spells" on another.
And the spells are more like the keywords associated with the action that occurs.
There are many flaws, such as the inventing spells, and using spells that you don't know what do like Harry with "Sectumsempra".
But it makes sense for younger wizards and witches who can do things without realizing it, or activating their powers in times of emotional distress.
