Bohr’s horseshoe
It is said that a visitor once came to the home of Nobel Prize–winning physicist Niels Bohr and, having noticed a horseshoe hung above the entrance, asked incredulously if the professor believed horseshoes brought good luck. “No,” Bohr replied, “but I am told that they bring luck even to those who do not believe in them.”
This story is probably apocryphal, but it is nevertheless quite true. It would be irrational not to hang a horseshoe above your door. If it doesn’t work, nothing happens. If it does work, you will be protected by it. It cannot possibly do any harm, and there is a chance, even if it’s a remote chance, that it will do good. This proves that materialists who don’t take such measures are in fact acting irrationally; they believe dogmatically that these things do not work, and therefore will not even risk trying them.
I don’t have a horseshoe above my door, but that’s because I live in an apartment building, and people would get angry with me if I did it. Also, I don’t know where to get a horseshoe.