[briantakita]

http://en.wikipedia.org/wiki/Superstition

> Superstition is the belief in supernatural causality

But then the influenced people become the causality of their actions. These root "superstitious" influences would then exist in concept and have a real effect. Note that conceptual existence is enough to influence intelligent beings who can recognize these concepts.

There's also effects that aren't explained by science, yet. That is a playground for all sorts of possibilities.