Great Regulars: If you say, "If I turn off the lights,

I'm afraid the shadows on the wall will turn into demons," when you turn out the lights, the shadows on the wall will probably turn into demons because that is your preconception. And once preconceptions enter the brain, they're hard to get rid of, kind of like cockroaches:

And where there's one there's probably a million
more who lie and laugh in cracks close by.
At first they seem so pitiful and base
feeding on what we leave behind.

from Kristen Hoggatt: The Smart Set: Ask a Poet: Quitting Time?

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