My undergrad Philosophy of Religion prof defined “superstition” by breaking it down into its component parts: Latin super, “over” + stitio, “standing” (< stare, “to stand”).

“A superstition is just an old belief that has 'stood over' from the past,” he said.

Of course, he was indulging in what's known as the “etymological fallacy.” Breaking a word down into its constituent parts may (or may not) give you some idea of what the word may have meant originally, but the simple fact of human language is that words change meaning over time.

(His favorite philosopher was Schleiermacher. Boy, did he ever hate my final paper: “Polytheism Reconsidered,” based on David Miller's The New Polytheism.*)

In this case, though, I think that he's reading “stand over” wrongly. (In fact, I would say that his reading of superstition is a culturally Christian reading.) For the Romans, “old” implied, not outmoded and left-over, but integrity, trustworthiness, authority.

I suspect that for the Romans, “stand over” implied, instead, threat.

A belief becomes a superstition when it takes over.

To say, then, that a belief is a superstition says nothing about the belief's truth or falsehood. It only observes that the belief has become deleterious to the believer. Belief that paralyzes or induces fear becomes superstition. To believe (to take only one example) in germs is one thing. To live in fear of germs is another.

Any belief, then, whether true or not, can become a superstition.

Caveat credens: Let the believer beware.

*He sure was a prince of a guy, though. Although he disagreed with it, he gave me an A on the paper because I'd argued it well. Now that's intellectual integrity.)

David L. Miller (1974), The New Polytheism: Rebirth of the Gods and Goddesses. Harper & Row.