[He gave Conan an appraising look. The kid clearly had a stark scientific view of the world that was typically difficult to counter, but he couldn't deny any open attempt to listen.]

That depends on what sort of explanation you're looking for. Even in my own world, exactly what or where magic comes from isn't known. It seems beyond explanation because we lack the ability to properly do so, but that isn't to say it's beyond the ability to define.