What is it a witch is doing when she mixes up some foul concoction, or lights a black candle, or casts a spell? I am not asking what her intent is, but by what mechanism does she hope to bring about the intended effect?
Well, by magic. So what is magic?
Magic is an attempt to harness a natural, but occult, mechanism, to bring about an effect. Occult means hidden, or rather (in this context) known only by adepts. So magic is science, or a kind of technology.
This also follows if the witch is calling on a “spirit” or “entity” to do her bidding. She expects that this spirit will use the means at its disposal, its natural means, to bring about the effect.
It is not that this natural mechanism is easy to implement or approachable by every person. It does not even have to be a known mechanism. Most people have no idea how cars work. They know that if they (these days) press the ON switch, the motor starts and the car goes. In the same way, the witch can, in the absence of any theory how her magic works, press a “button” and hope the spell goes.
Of course, witches are wrong about how effects come about. Their magic doesn’t work (I do not dismiss that people can contact spirits or entities, i.e. demons, which can bring about effects by natural means). But that doesn’t matter, because they think they are right. We’re only interested in what they believe they are doing. And what they believe they are doing is obscure or arcane science.
Arthur C Clarke, as every literate person knows, said, “Any sufficiently advanced technology is indistinguishable from magic.” This is almost right. He could have said science is magic, or magic is science, and have been done with it.
By natural means I have in mind a process that exists, that can be “tapped”, like starting a car is a process that can be tapped if one has the proper fob. Magic does not create the process; it uses processes that are thought (incorrectly, as all evidence attests) to exist.
Contrast magic with miracles. When Jesus turned the water into wine, he did not use magic. It is not that there is not some obscure, hugely energy-expensive mechanism to transform the mass of water (and trace chemical) molecules into ethanol and other molecules. This might exist. But Jesus certainly did not use it, not having the means to employ such a thing.
Instead, Jesus changed the essence of the material, the form of it, into something new. Changing the essence of a thing requires unnatural, supernatural powers; indeed, abilities no science can ever reach. Science (or technology) can only twist the pre-existent dials of nature. It can’t create those dials. Miracles aren’t interferences in the “laws of physics”, they are changing of the very nature of nature.
This is why you have to pray for a miracle, because you can never do it yourself. Miracles by definition require the cooperation of God.
Superstition is thus obviously a form of magic, of science. It (and even magic) works variously well, depending on how closely the superstitious act accords with nature. It fails when there is no accord, where the user has mistaken correlation for causation.
Is a Christian lighting a candle attempting superstition? Certainly this is not an attempt at magic. But perhaps superstition is a good charge.
In some cases the charges of superstition are probably true. None of us are perfect. But most of the time the Christian uses the candle as a means of prayer, a devotional object, therefore there is no sin; that is, no attempt at magic.