Not sure how serious you’re being but I’m comfortable in saying that:
Voodoo, Nostradamus, superstitions, liberalism and astrology are all equally useless garbage and those who practice/ascribe to/believe in any of them are intellectually deficient.
I’ll give a pass to those under the age of, let’s say... 15.
Your litmus test achieves two things: it thins out honest people [the vast majority of adults believe in the supernatural], and it thins out people who take history seriously. Joan of Arc, for example. Great way to size people up! /sarc